bluuebunny/crossref_metadata_2025 huggingface dataset:
Serum and cerebrospinal fluid levels of fluphenazine–relationship to treatment response in schizophrenic patients
Authors: Rimón Ranan , Kampman Reima , Laru‐Sompa Raili , Wiles D. H.
Published: January 2005

Serum and cerebrospinal fluid (CSF) concentrations of fluphenazine (FPZ) were measured during nine weeks of FPZ medication in 28 patients with acute symptoms of schizophrenia. A significant correlation was found between the serum and CSF FPZ values (r = 0·70, p < 0·001) throughout the entire study. Patients exhibiting marked clinical improvement (MCI) had higher levels of serum and CSF FPZ than did patients showing only slight clinical improvement (SCI) or those with no treatment response (NTR). The differences between the MCI and the NTR group were at most observation points statistically significant (p < 0·05). The figures of the SCI group formed an intermediate curve between the serum and CSF FPZ curve of the MCI and the NTR patients.

The serum and the CSF levels of FPZ were not significantly related to such variables as age, sex, duration of illness, number of previous psychotic episodes, or subtype of schizophrenia.
The effects of single and repeated doses of oral scopolamine, cinnarizine, and placebo upon psychological performance and physiological functioning
Authors: Parrott A. C. , Golding J. F. , Pethybridge R. J.
Published: January 2005

The present study was one in a series in the Institute of Naval Medicine's Motion Illness Project. A battery of psychological performance tests (producing 26 indices of mental and hand‐‐eye co‐ordination), together with visual near fixation point, resting heart rate and a self‐rated feeling state questionnaire, were used to compare the effects of thrice‐daily oral doses of scopolamine (0.6 mg), cinnarizine (30 mg) and a lactose placebo in a double‐blind crossover trial on 12 healthy male volunteers. Measurements were made 1–2 and 5–6 h after the initial dose, then the next day following the last successive dose (1–2 and 5–6 h after the fourth dose; or 25–26 and 29–30 h after the initial dose). Scopolamine demonstrated clear physiological effects, with reduced heart rate from the first oral dose onwards, and visual near‐point values increasingly distant over successive doeses. Cinnarizine did not produce significant physiological changes. Neither drug produced significant effects on subjective mood. Significant ANOVA drug effects or drug × time interaction effects were present with five out of the 26 performance variables: logical reasoning error, memory word‐recall errors; continuous four choice reaction time; concept identification time; SERS task commission error. However only two of these (memory error, four choice reaction time) demonstrated patterns of effect which were considered to be attributable to the drugs. Both cinnarizine and scopolamine impaired memory error and four choice reaction time. Only for visual near‐point with scopolamine was there evidence that repeated dosing led to increasing physiological/mental performance effects.
Sulpiride in negative schizophrenia: A placebo‐controlled double‐blind assessment
Authors: Soni S. D. , Mallik A. , Schiff A. A.
Published: January 2005

Twenty‐four chronic schizophrenic long‐stay hospital patients were identified, who had not received neuroleptic drugs for 8–30 (average 8 months) and met or exceeded a minimum criterion of severity of negative symptoms. They were rendomly alocated to either sulpiride 200 mg twice daily or matching placebo, on a double‐blind basis for 12 weeks. The results showed that low‐dose sulpiride was significantly better than placebo in relation to improvements in negative symptoms. The changes in social behaviour were complex and not obviously related to symptom improvement; exhibited abnormal behaviour, a major factor in preventing successful return to the community, consistently improved only on the active drug.
Significantly increased urinary free cortisol excretion in melancholic depressed females during L‐tryptophan loading
Authors: Maes M. , Minner B. , Suy E. , D'hondt P.
Published: January 2005

To assess the status of serotonergic neurotransmission in depressed females, the authors examined the excretion of free cortisol in 24 h urine both before and after administering 5 g L‐tryptophan (L‐TRP) orally. The depressed patients were classified according to the DSM‐III into minor, simple major and major depression with melancholia. We found a significant, enhacing effect for L‐TRP on urinary free cortisol (UFC) excretion. The absolute increments in UFC induced by L‐TRP were significantly higher in melancholic females as compared to minor and simple major depressives. We found no differences among the DSM‐III groups in the availability of L‐TRP to the brain, 9 h after L‐TRP administration.
Possible mechanisms for the presumed interaction between lithium and neuroleptics
Authors: Von Knorring L.
Published: January 2005

All the case reports describing neurotoxicity following combined lithium and haloperidol treatment could well be consistent with lithium toxicity alone. Pharmacokinetic and pharmacological explanations are considered. The effects of co‐administered lithium and neroleptic treatment on fluid balance mechanisms and intracellular lithium concentrations may be associated with increased lithium toxicity.
Clinical and functional correlates of a dopamine D3 receptor polymorphism
Authors: Crocq Marc Antoine , Duval Fabrice , Mayerova Antonia , Sokoloff Pierre , Mokrani Marie Claude , Macher Jean Paul
Published: January 2005

This is a review of our research on dopamine receptor D3 (DRD3) gene polymorphism in psychiatric patients. We found that heterozygosity at a diallelic Ball polymorphic site in the first exon of the DRD3 gene was associated with schizophrenia, as did another group (Mant et al., 1994). However others did not reproduce our findings and raised doubts about a possible role of the DRD3 in schizophrenia. More recently, we found that homozygosity for allele 2 at the same site was associated with lower cortisol and ACTH responses to apomorphine. We had also previously reported lower ACTH and cortisol responses to apomorphine in paranoid schizophrenics compared to controls (Mokrani et al., in press). This suggests that DRD3 polymorphisms might be associated with functional differences that could secondarily influence the expression of schizophrenia, in spite of the lack of clear association with schizophrenia. More generally, classical association studies may be limited in their power to prove or disprove minor gene effects in schizophrenia because the disorder is heterogeneous and various genes may have additive effects in different patients. Biological measures that are closer to gene effects may be a better way to test candidate genes than the association with a complex clinical phenotype.
Hypophagic, endocrine and subjective responses to m‐chlorophenylpiperazine in healthy men and women
Authors: Cowen P. J. , Sargent P. A. , Williams C. , Goodall E. M. , Orlikov A. B.
Published: January 2005

We studied the effect of the 5‐HT receptor agonist, m‐chlorophenylpiperazine (mCPP) (0.4 mg orally), on food intake, plasma prolactin and subjective state in 24 healthy male and female volunteers, using a double‐blind, placebo‐controlled design. mCPP lowered food intake, and increased plasma prolactin to the same extent in both sexes. Increased anxiety ratings, however, occurred more in females. Other mCPP‐induced subjective changes in nausea, light‐headedness and hunger did not distinguish the sexes. There was no significant correlation between the decrease in food intake produced by mCPP and any of the subjective ratings. Overall, the data indicate that mCPP produces significant hypophagia in both men and women. The greater anxiogenic effect of mCPP in female subjects is of interest in view of the increased prevalence of clinical anxiety disorders in women.
High dose tertiary amine tricyclic antidepressants in the treatment of severe refractory depression: The central role of plasma concentration estimations
Authors: Hodgkiss A. D. , McCarthy P. T. , Sulke A. N. , Bridges P. K.
Published: January 2005

The relationships between dosage, plasma concentration, antidepressant response and toxicity were investigated in 24 highly selected patients with severe, refractory major depression who were prescribed amitriptyline, clompramine or dothiepin at high dosage (150–525 mg/day), usually in combination with lithium or other psychotropics. of serious adverse effects 83 per cent were encountered when tricyclic antidepressant (TCA) plasma concentrations exceeded 400 mcg/1. Therapeutic drug monitoring of high dose TCAs is useful in minimizing the risk of toxicity and in revealing poor compliance, undertreatment and pharmacokinetic interactions which can mitigate against drug efficacy. The value of carbamazepine in the management of refractory depression in the context of unipolar affective disorder is put into question.
Nogo signaling and non‐physical injury‐induced nervous system pathology
Authors: Teng Felicia Yu Hsuan , Tang Bor Luen
Published: January 2005

The Nogo gene products were described first as myelin‐associated inhibitors that prevent neuronal regeneration upon injury. Recent findings have also implicated Nogo in several neuronal pathologies that are not induced by physical injury. Nogo‐A may be an important determinant of autoimmune demyelinating diseases, as active immunization with Nogo‐A fragments attenuates the symptoms of experimental autoimmune encephalomyelitis (EAE). Nogo‐A levels are elevated markedly in hippocampal neurons of patients with temporal lobe epilepsy (TLE), in brain and muscle of patients with amyotrophic lateral sclerosis (ALS), and in schizophrenic patients. Concrete evidence for a direct role of Nogo‐A in the latter neuropathies is not yet available, but such a role is logically in line with new findings associated with localization of Nogo‐A and Nogo–Nogo‐66 receptor (NgR)‐mediated signaling. We speculate on possible linkages between the effect of aberrant elevation of Nogo levels and the signaling consequences that could lead to nervous system pathology. © 2004 Wiley‐Liss, Inc.
Elevated endogenous GABA level correlates with decreased fMRI signals in the rat brain during acute inhibition of GABA transaminase
Authors: Chen Zhengguang , Silva Afonso C. , Yang Jehoon , Shen Jun
Published: January 2005

Vigabatrin and gabaculine, both highly specific inhibitors of GABA (γ‐aminobutyric acid) transaminase, cause significant elevation of endogenous GABA levels in brain. The time course of GABA concentration after acute GABA transaminase inhibition was measured quantitatively in the α‐chloralose‐anesthetized rat brain using in vivo selective homonuclear polarization transfer spectroscopy. The blood oxygenation level‐dependent (BOLD) effect in functional magnetic resonance imaging (fMRI) has been considered to be coupled tightly to neuronal activation via the metabolic demand of associated glutamate transport. Correlated with the rise in endogenous GABA level after vigabatrin or gabaculine treatment, the intensity of BOLD‐weighted fMRI signals in rat somatosensory cortex during forepaw stimulation was found to be reduced significantly. These results are consistent with previous findings that inhibition of GABA transaminase leads to augmented GABA release and potentiation of GABAergic inhibition. © 2004 Wiley‐Liss, Inc.
The effect of the chronic administration of D‐amphetamine upon circadian changes in amino acids in the pineal and pituitary glands of the rat
Authors: Leonard B. E. , Neuhoff V. , Tonge Sally R.
Published: January 2005

The formation of dansyl derivatives of amino acids, 5‐hydroxyindoleacetic acid and histamine, and their separation on polyamide plates provides a reliable and sensitive method for studying circadian changes in single pineal and pituitary glands of the rat. There appears to be no correlation between the circadian changes in concentrations of these substances in the pineal and pituitary glands.

Chronically administered D‐amphetamine altered the circadian rhythms of five amino acids in the pituitary, including the putative transmitters taurine, glycine, and glutamate; in the pineal gland only the rhythmical changes of lysine and 5‐hydroxyindoleacetic acid were affected.
Six‐month follow‐up in weanling rats with ventromedial and dorsomedial hypothalamic lesions: Somatic, endocrine, and metabolic changes
Authors: Bernardis L. L. , Goldman J. K. , Chlouverakis C. , Frohman L. A.
Published: January 2005

Thus far both the weanling rat ventromedial and dorsomedial syndrome have been investigated in only two and three‐week studies. The present data are derived from a six‐month study. Food intake and body weight and length changes were recorded weekly or bi‐weekly and endocrine and metabolic parameters were assessed at sacrifice. Rats that had received ventromedial hypothalamic lesions shortly after weaning showed all the changes noted in previous short‐term studies, i.e. normal body weight gains and food intake but increased carcass fat content. In addition, they manifested a slight hyperglycemia, normal free fatty acid levels and slowing‐down of lipogenesis. Rats that had received dorsomedial lesions shortly after weaning also showed changes previously reported in short‐term experiments. These include reduced ponderal and linear growth and food intake, but normal carcass composition and growth hormone levels. In addition, they showed a slight improvement of hypophagia with time, and at sacrifice hypoglycemia and low free fatty acid levels. Incorporation of glucose into fat pad glycogen and CO2 was decreased. In diaphragm, glucose incorporation was increased in both total lipid and fatty acids. The data demonstrate that both hypothalamic syndromes change with time, but not necessarily in a progressive manner. They also show that destruction of two so closely appositioned hypothalamic structures brings about entirely differnt and, in some parameters, opposite changes.
Difference in occipital cortical synapses from environmentally enriched, impoverished, and standard colony rats
Authors: Diamond Marian C. , Lindner Bernice , Johnson Ruth , Bennett Edward L. , Rosenzweig Mark R.
Published: January 2005

Initial and replication experiments were studied with littermate, S1, male rats 25–55 days of age placed in enriched (EC), standard colony (SC), and impoverished (IC) environments. Measurements of the length of postsynaptic thickenings were taken from asymmeterical axodendritic synapses in layer IV of the dorsal medial occipital cortex. This experiment differed from others of this nature, for animals from both experimental conditions were compared with the standard colony animals. The 8% (p < 0.01) difference in postsynaptic thickening length between 675 synapses from EC and 680 synapses from IC was primarily due to the IC, as can be seen by comparing both with the SC.

The number of synapses per unit area of neuropil was 15% (p< 0.01) more in the IC than in the EC and this difference was primarily due to impoverishment. Both the original and the replication experiment verified this direction of change. Thus, environmental experience does significantly affect synaptic length and number, although the large magnitude previously reported by Møllgaard et al. (1971) was not confirmed in the present experiments. The 7% cortical depth difference between the enriched and impoverished animals was seen to be attributed to both conditions when each was compared with the standard colony rats. The plasticity of synaptic dimensions is discussed in relation to our previous work and to work of others.
Somatic evoked response components and recovery functions in subjects with mu and alpha rhythms
Authors: Velasco Marcos , Berrondo Luisa , Olvera Alfredo , Velasco Francisco
Published: January 2005

Subject with prominent rolandic mu and alpha rhythms showed similar late somatic evoked response (SER) components but different SER recovery functions.

A late P5x component was present when SER were superimposed on mu and alpha rhythms spontaneously recorded from the rolandic region of inattentive individuals. Since P5x was not present in other inattentive subjects unless SER were superimposed on a rhythmic rolandic activity evoked by an attentive situation, it seems reasonable to assume that the p5x component is partially due to spontaneous or evoked rolandic EEG rhythmicity.

In addition, single propioceptive stimuli produced blocking of mu rhythm and a flat recovery function of the P5a component. In contrast, similar stimuli produced an enhancement of alpha rhythm and periodic amplitude modulation curve of the P5a component. These results suggest that the P5a component is mediated by the same neurophysiological mechanisms which block or modulate the spontaneous rolandic EEG rhythms.
Studies on neuronal lipid
Authors: Tamai Yoichi , Araki Shigeko , Komai Yuichi , Satake Mei
Published: January 2005

The procedure for bulk preparation of nerve‐cell perikarya from pig brain‐stem is briefly described. This method has definite merits with regard to the preservation of the intracellular structures as well as the preservation of the processes.

The chemical composition of the isolated nerve‐cell perikarya is presented. The nerve‐cell perikarya are characterized by the absence of cerebroside and sulfatide. Diffuse distribution of ganglioside on the cell surface is suggested. The lipid content of the nerve‐cell perikarya isolated by different methods is discussed.

Lipid composition of the invertebrate nervous tissue is discussed.

The submicrosomal membranes of rat brain are isolated, and their chemical and morphological properties are discussed. Ribosome‐free membranes are characterized by the high content of glycolipids including gangliosides, as well as by the high activity of Na, K‐ATPase, whereas ribosome‐bound membranes are characterized by the absence of glycolipids, as well as by the low activity of Na, K‐ATPase. The molecular organizations of lipid in submicrosomal membranes are demonstrated.
Comparison of visual and tactile learning in octopus after lesions to one of the two memory systems
Authors: Bradley E. A. , Young J. Z.
Published: January 2005

Sets of animals with lesions to either the vertical lobe or median inferior frontal lobe were trained first visually and then by touch. Lesions of the vertical lobe system did not affect the increase produced by food in tendency to attack a moving figure in the visual field. Any lesion that interrupted the circuit through the vertical lobe greatly impaired the capacity to inhibit attacks on crabs when these attacks resulted in shocks. Removal of the median inferior frontal lobe did not impair this capacity to learn not to attack a crab in the octopus's visual field.

The Capacity to learn to respond positively to a black disc but to avoid a white one was grossly impaired by an interruption of the vertical lobe circuit. After such operations the animals showed a strong preference for white over black. The capacity to learn to discriminate between black and white was not affected by removal of the median inferior frontal lobe. Animals with interruptions of the vertical lobe circuit could learn to make discrimination between white as a positive figure and black as a negative one, but they made more mistakes than controls. Most mistakes consisted of attacks on the negative (black) figure, but there were also some failures to attack the white.

In tactile discrimination between rough and smooth spheres given successively, animals with vertical lobe lesions were, under some circumstances, less accurate than controls. They took more objects than controls. They were less able than controls to reverse the discrimination. After removal of the median inferior frontal lobe tactile discrimination was greatly impaired. The animals showed a strong preference for rough objects and could not learn to take smooth objects. However, they showed improvement in discrimination when trained with smooth negative and are therefore not wholly incapable of long‐term memory storage.
In vivo measurement of 32P in the brain of a freely moving rat
Authors: Mayevsky A. , Samuel D. , Friedland S. S. , Ewins J. H.
Published: January 2005

A new method for measuring the uptake of materials labeled with radioactive phosphorus (32P) in the brain of a freely moving rat is described. The rat of uptake in the brain of a single animal of 32P‐labeled phosphate was compared to the uptake rate in the animal's blood or liver. A comparison was made between the uptake following an intravenous (IV) or an intraperitonel (IP) injection. The effect of convulsions caused by injections of metrazol on the kinetics of 32P uptake in the brain is described.
Associative recall and formation of stable modes of activity in neural network models
Authors: Wigström Holger
Published: January 2005

Models of neural networks with recurrent inhibition are studied, as well as one model which also includes recurrent excitation. The models are intended as possible descriptions of the cerebral cortex.

Each network model is composed of neuron models called pyramidal cells and stellate cells in accordance with the names of two types of cells in the cortex. Inputs and outputs of the network are connected to the pyramidal cells while feedback is provided by the stellate cells. Connections within the network are random.

During a learning phase the pyramidal cell excitatory synapses become facilitated according to a two‐ conditional facilitation rule. This is the basis of the model's ability for associative learning. The associative retrieval of information can be studied during a subsequent association phase. This has been done by simulation on a digital computer.

It was shown that all of the models considered can be designed to perform a so‐called decision‐making function. This means that if the associating input pattern is similar to several patterns which occurred during learning the model can decide which similarity is greatest by responding with the appropriate associated pattern.

The model also including recurrent excitation differs from the simpler models in that it can become stabilized in so‐called stable modes of activity which are self‐sustaining and remain even after the input has been turned off. Normally, only one stable mode can be active at a time. However, through careful choice of construction parameters it was possible to obtain a model in which a maximum of two stable modes could be activated independently of each other.

Physiological and psychological interpretations are discussed and so are the limitations of the models, which are evident in certain situations.
Neuronal control of neurotransmitters biosynthesis during development
Authors: Giacobini Ezio
Published: January 2005

Studies on neuronal control mechanisms of neurotransmitters biosynthesis during the development of peripheral and centralautonomic synapses are reviewed. Particular emphasis is placed on investigations of developing peripheral sympathetic ganglia and brain in chick embryo and chick.

Studies on the development of autonomic neurons and synapses under different pharmacological conditions are reported. Principally the effect of (a) the administration of drugs and precursors such L‐dopa, 3H‐dopa, 6‐OH dopa; (b) the prenatal administration of reserpine; (c) the blockade of cholinergic receptors; (d) the nerve growth factor (NGF) is analyzed.

Results of developmental studies on chick ciliary ganglia are summarized.

The review particulary underlines the importance of combining the use of sensitive microchemical methods to pharmacological tools in exploring the development of regulatory mechanisms at the cellular level.
Food intake of weanling rats with lesions in the ventromedial and dorsomedial hypothalamic nuclei in response to intragastric loading and caloric density manipulation
Authors: Bernardis Lee L. , Border John R.
Published: January 2005

Male rats received bilateral electrolytic lesions shortly after weaning in the ventromedial (VMN) and dorsomedial (DMN) hypothalamic nuclei, respectively. A third group of rats served as sham‐operated controls. The animals were subjected to intragastric preloading with 33% d‐glucose and egg‐white solutions and a 33% corn‐oil suspension, and ad libitum feeding was assessed hourly for the first 7 hr after preloading. The pattern of food‐intake depression was similar in all groups but the quantitative greatest depression was found in the DMN rats. The response of these three groups of animals to a diet diluted with 20% alpha cell, a nonnutritive bulker, showed an initial failure to meter calories by both VMN and DMN rats which, however, was compensated for during the remainder of the 24‐hr test period. In response to a 50% glucose‐chow mixture, both VMN and DMN rats, as well as the controls, showed the same pattern and behaved like mature dynamic hyperphagic rats inasmuch as they did not eat more of this mix than of the standard diet. After a 48‐hr fast, both VMN and DMN rats showed refeeding hypophagia rather than hyperphagia. The data suggest that Panksepp's contention that the VMN in the mature rat is involved in long‐term satiety regulation may be extended to the weanling rat with VMN destruction. Thus, this controlling role appears established early in ontogeny.
Glucose preference and caloric regulation in weanling rats with ventromedial and dorsomedial hypothalamic lesions
Authors: Bernardis Lee L. , Border John R.
Published: January 2005

Weanling male rats received electrolytic lesions in the ventromedial (VMN) and dorsomedial (DMN) hypothalamic nuclei, respectively. A third group of rats served as sham‐operated controls (CON). After the two hypothalamic syndromes had been well established, the animals were subjected to (1) a glucose preference test assessing the choice between a 10% w/v and a 35% w/v d‐glucose solution, and (2) a test examining the anorexigenic effect of intraperitoneally injected glucose. Weanling rats with VMN lesions, like their mature counterparts, consistently preferred the stronger over the weaker glucose solution throughout the experiment (16 days). Weanling DMN rats, on the other hand, showed a bimodal response, initially like that of the CON rat, toward the end of the experiment, like that of the VMN rats. The weanling CON animals behaved differently from their mature counterparts, inasmuch as their preference for the dilute solution became evident only toward the latter part of the test. An analysis of the calorie intake shows that calories from glucose are similar in all three groups of rats, that the pattern and magnitude of caloric intake in DMN and CON rats are almost identical, and that the total calorie intake (from chow plus glucose) is reduced in the DMN rats because the calorie component from chow is profoundly reduced. In response to intraperitoneally injected glucose, VMN rats show a longer depression of food intake than has been reported for mature VMN rats. The CON and DMN rats recovered quicker and reached pre‐injection levels of food intake sooner than the VMN rats. The data indicate that in the weanling VMN rat, as in its mature counterpart, the VMN are involved in long‐term feeding behavior and do respond to the metabolic signal arising from administered glucose. Nevertheless, the principle factor in their preference seems to be taste rather than solely a metabolic signal. The data also show that the DMN are less involved in this sensing and integrating mechanism. In essence, the DMN rat functions quite normally, but its control system is set at a subnormal level.
Effects of specific brain lesions on the thermal responses of rats to d‐amphetamlne
Authors: Yehuda Shlomo
Published: January 2005

Lesions in either olfactory bulb or in area postrema modify the amphetamine‐induced paradoxical thermoregulatory behavior, although these lesions in no way affect amphetamine‐induced hypothermia. In addition, these lesions lead to complicated patterns of thermoregulatory behavior. These results can be best explained by assuming that lesions in one part of the brain monoamine system might affect levels and turnover of monoamines in remote parts of the brain. Among d‐amphetamine behavioral effects which are known to be mediated by central dopaminergic neurons are hypothermia in animals placed in a cold environment, and paradoxical thermoregulatory behavior (this involves the movement of animals away from the heating source despite hypothermia). This latter effect requires intact alpha norepi‐ nephrine receptors. It seems that neither type of lesion affected dopaminergic neuronal activity in the brain. However, norepinephrine activity in the brain was affected by the area postrema lesion as well as by the olfactory bulb removal.
The effect of α‐melanocyte stimulating hormone (α‐MSH) on the metabolism of blogenlc amines in the rat brain
Authors: Leonard B. E. , Kafoe W. F. , Thody A. J. , Shuster S.
Published: January 2005

The effect of the chronic administration of α‐MSH on the incorporation of tritiated tyrosine into noradrenalin and dopamine and of tritiated tryptophan into serotonin was studied in different regions of the rat brain. α‐MSH increased the incorporation of tritiated tryptophan into serotonin in the cortex and slightly decreased that of tyrosine into the dopamine in the hypothalamus. As the brain concentration of serotonin was unchanged in the animals treated with α‐MSH, it is suggested that some of the changes in behavior, which other investigators have found following the administration of peptides containing the same sequence of amino acids to that found in MSH, could be associated with an increased turnover of cortical serotonin.
A study of 3H‐L‐fucose‐containing glycoproteins of the crude synaptosomal fraction, obtained from rat brain regions at various ages
Authors: Davis Leonard G. , Brunngraber Eric G. , Routtenberg Aryeh
Published: January 2005

The frontal cortex showed a marked elevation of incorporation of H‐L‐fucose into glycoproteins of the crude synaptosomal fraction at 9 days of age. The effect was observed at both 8 and 24 hr after intraperitoneal administration of radioactive fucose. The elevation was absent in the 1, 5, 16, and 25‐day‐old frontal cortices. It was also absent in the hippocampus and cerebellum at all ages studied.

Fucose‐labeled glycoproteins of high molecular weight in the crude synaptosomal fraction, as separated by polyacrylamide gels, were preferentially labeled in the hippocampus, frontal cortex, and cerebellum at all ages studied. In general, these glycoproteins became less prominent in the oldest animals studied (25 days). However, the relative amount of these glycoproteins varied with age of the animal, time between administration of isotope and sacrifice, and with the brain areas studied.
Brachium conjunctivum‐red nucleus synaptic system in the baboon
Authors: Huffman R. D. , Davis R.
Published: January 2005

Electrophysiological properties of the brachium conjunctivum‐red nucleus (BR‐RN) synaptic system were studied in barbiturate‐anesthetized baboon (Papio). Topographic recordings from the mesencephalon demonstrated that most of the BC‐evoked activity was restricted to an area histologically identified as red nucleus; however, some brachium‐evoked activity was recorded from the surrounding mesencephalic reticular formation. Short latency BC‐evoked activity was also recorded from the pons in the region of nucleus reticularis tegmenti pontis. The majority of the BC fibers were found to conduct at a rat of 44 m/sec; a second group of BC fibers with a slower conduction velocity of 23 m/sec was also observed. Brachium‐evoked responses recorded from magnocellular and parvicellular RN neurons were short latency responses consistent with monosynaptic activation of these RN neurons by the BC fibers. The BC‐RN synaptic system was found to be a very secure synaptic system and could transmit activity at high rates of stimulation with little or no failure. The responsiveness of the BC fibers was found to be similar to that of optic nerve fibers and pyramidal tract fibers, both of which have been characterized as being similar to peripheral A fibers. The responsiveness of the BC‐RN synaptic system began to decrease 5 msec after a single or repetitive transmission and was reduced to about 50% of normal responsiveness at 34 msec. This period of reduced postsynaptic responsiveness was associated with a reduction in presynaptic input to RN and suggest that a disfacilitation at the level of the deep cerebellar nuclei may be in part responsible for the subnormal responsiveness of the BC‐RN synaptic system.
Behavioral evidence showing the predominance of diffuse pain stimuli over discrete stimuli in influencing perception
Authors: Anderson Kenneth V. , Pearl Gary S. , Honeycutt Clegg
Published: January 2005

This experiment was directed toward determining the relative effectiveness of discrete and diffuse pain stimuli in influencing perception and behavior. Shocks to the footpads were use to activate the discrete pain pathways. In the first phase of this experiment, cats were trained to escape from foot shock in a shuttle box. Current applied to the feet was varied in ascending and descending sequences for each animal according to the psychophysical method of limits and each animal was trained until stable thresholds for escape responding were achieved. In the second phase of the experiment, the effect on behavior of simultaneous activation of both the discrete and diffuse pain systems was assessed. The principal finding in this experiment was that escape responding that was well established when foot shock was presented alone was routinely abolished on trials when tooth shock and foot shock were presented together. These results were interpreted as indicating that the diffuse pain system was prepotent in influencing behavior when both the discrete and diffuse pain systems were activated simultaneously.
Biological responsiveness to cholinesterase inhibition: A test for exploring the developmental maturity of the cholinergic system
Authors: Torre Carlo
Published: January 2005

The acute mortality caused by two irreversible inhibitors of cholinesterases [disiopropylfuorophosphate (DFP) and diethoxyphosphorylthiocholine, 217 MI‐phospholine iodide] has been investigated on chick embryos at different stages of development.

The results demonstrate that the above compounds do not show any acute lethal action when administered before the 9th day of incubation; on the other hand, the administration is regularly followed by death after the 9th day of incubation. The doses are comparable to those causing death in hatched chicks.

It has also been observed that no appreciable difference exists in DFP uptake from the yolk before and after the 9th day of incubation and that drug‐induced cholinesterase inhibition is of the same order of magnitude at any developmental stage; the compound pyridine‐2‐aldoxime methanesulfonate (2‐PAM) was a good antidote against DFP acute lethality.

It seems likely that between the 8th and the 9th day of incubation the target system of organophosphorus inhibitors, that is, the cholinesterase enzymatic system, reaches a new point of maturation.
Regional properties of dorsal and ventral hippocampus in suppression of intralaminar thalamic unit responses
Authors: Burchell Andrea , McKenzie J. S. , Rogers D. K.
Published: January 2005

In chloralose‐anesthetized. Flaxedil‐paralyzed cats, the suppression of extralemniscal thalamic units by the dorsal and ventral hippocampus was investigated. Unitary responses to test somatic stimuli, recorded in centrolateral and neighboring thalamic nuclei, were interacted with conditioning electrical stimulation in different regions around the hippocampal arch, including the parahippocampal gyrus (entorhinal and retrosplenial areas).

Stimulation of dorsal (DHC) and ventral (VHC) hippocampus suppressed roughly equal proportions of responses. However, within each of DHC and VHC, effectiveness depended on the region stimulated. In DHC, Fields CA1 and CA3, subiculum (SUB), and retrosplenial area, but not field CA4 with dentate gyrus (FD), while stimulation of CA1 or subiculum was almost ineffective at currents below 1.0 mA. In VHC the regions were ranked for effectiveness as follows: entorhinal cortex = CA3 > FD >SUB >CAI.

No topographic relationship was found between hippocampal region and thalamic loci for unit suppression. Lemniscal‐type unit responses in ventrobasal thalamus were unaffected by stimulation of the hippocampus or parahippocampal gyrus.

Interruption of the fornix‐fimbria system prevented suppression elicited from CA1 of DHC or from CA3 of VHC, but not from FD of VHC. It had no effect on suppression elicited from retrosplenial or entorhinal cortex.

Hippocampal regional variation of effectiveness in suppressing extralemniscal pathways may contribute to the differential behavioral involvements reported for different hippocampal structures.
Membrane protein and glycoprotein composition of beef brain synaptic vesicles
Authors: Richter‐Landsberg Christiane , Neuhoff Volker , Waehneldt Thomas V.
Published: January 2005

Synaptic vesicles were isolated from adult bovine cortical gray matter by differential centrifugation and membrane filtration of a hypoosmotically lysed crude mitochondrial fraction. Vesicle preparations were analyzed for purity by electron microscopy and enzyme assays. Polyacrylamide gel electrophoresis of SDS‐solubilized and 2‐mercaptoethanol‐reduced vesicle membrane proteins revealed 4 major proteins with molecular weights ranging from 17,000 to 60,000, and about 10 minor proteins with molecular weights up to 170,000. The protein profile of the Triton X‐100‐extracted vesicle membranes was less complex, with 1 major protein and 5 minor bands. The major protein of the Triton extract was identified as a glycoprotein with a molecular weight of 45,000. Two additional minor PAS‐positive bands were seen, with molecular weights of 78,000 and 95,000.
Quipazine exacerbation of a hyperkinetic syndrome: Involvement of brain dopamine and serotonin
Authors: Langlais P. J. , Gabay S.
Published: January 2005

Quipazine (5–25 mg·kg−1, s.c.) was given to rats in which a hyperkinetic syndrome had been previously induced by administration of β;,β′‐iminodiproprionitrile (IDPN). Quipazine produced a significant increase in the circling behavior and choreiform head and neck movements, characteristic of the syndrome. This response could be blocked by pretreatment with the serotonin antagonists, SQ10, 631 (25 mg·kg −1, i.p.) and methysergide (5.0 mg·kg−1, i.p.), as well as the dopamine receptor antagonist, haloperidol (0.5 mg·kg−1, i.p.). These observations are discussed with respect to the nature of the involvement of brain serotonergic and dopaminergic systems in quipazine action on these hyperkinetic disturbances.
Response properties of cells in the dorsal lateral geniculate nucleus of the albino rat
Authors: Anderson Kenneth V. , Lemmon Vance , Rosing Howard S.
Published: January 2005

The response patterns of cells in the dorsal lateral geniculate nucleus of the albino rat were studied in order to examine the functional organization of the lateral geniculate nucleus. Both photic stimulation and electrical stimulation of the optic tract were used to activate single units in the lateral genicualte nuclei. Three different types of response patterns were fond for principal cells, while interneurons all had similar response patterns. The first class of principal cells, E‐S cells, responded to stimulation with a period of excitation, followed by a period when activity was suppressed. A second class of cells, S cells, responded to photic stimulation with an initial period when activity was suppressed. The final class of cells, E cells, responded with a period of excitation followed by a return to spontaneous rates of firing. The response patterns of E cells suggest that this type of principal neuron does not receive feedback inhibition of the type proposed in previous models of the lateral geniculate nuclei. Based on these and other and other observations, a new model of the functional organization of the lateral geniculate nuclei is proposed.
Amino acid incorporation into total protein and levels of S‐100 protein in discrete rat brain areas after prolonged protein or amino acid restriction
Authors: Rosengren L. , Wronski A. , Haglid K. G. , Jarlstedt J. , Rönnbäck L.
Published: January 2005

Young adult rats were fed an isocaloric diet for 28 days. The diet consisted of either 22% casein, or protein‐restricted food consisting of a 5% mixture of soy and whey protein, or a synthetic amino acid mixed diet devoid of the essential amino acids tryptophan, valine, lysine, and threonine.

The level of the nervous tissue‐specific S‐100 protein was quantified immunoelectrophoretically in 9 different brain areas. A marked decreased of S‐100 was observed in hippocampus and posterior part of the cerebellar vermis per g wet weight in protein‐restricted rats. An additional lowering was noticed in sensory motor cortex per mg soluble protein. This effect was potentiated with the amino acid deficient diet.

The in vitro incorporation of 3H‐leucine into cerebellar proteins was slightly decreased in the low protein‐fed rats, and more markedly decreased in those receiving an amino acid‐restricted diet.
Regional properties of dorsal and ventral hippocampus in suppression of intralaminar thalamic unit responses
Authors: Burchell Andrea , McKenzie J. S. , Rogers D. K.
Published: January 2005

In chloralose‐anaesthetized, Flaxedil‐paralysed cats, the suppression of extralemniscal thalamic units by dorsal and ventral hippocampus was investigated. Unitary responses to test somatic stimuli, recorded in centrolateral and neighbouring thalamic nuclei, were interacted with conditioning electric stimulation in different regions around the hippocampal arch, including parahippocampal gyrus (entorhinal and retrosplenial areas). Stimulation of dorsal (DHC) and ventral (VHC) hippocampus suppressed roughly equal proportions of responses. However, within each of DHC and VHC, effectiveness depended on the region stimulated. In DHC, fields CA1 and CA3, subiculum (SUB), and retrosplenial area, but not field CA4 or dentate gyrus, usually suppressed extralemniscal units at currents below 1.0 mA. In VHC, the most effective regions were entorhinal cortex, CA3, and CA4 with dentate gryus (FD), while stimulation of CA1 or subiculum was almost ineffective, at currents below 1.0 mA In VHC, the regions were ranked for effectiveness: Entorhinal cortex = CA3> FD > SUB > CA1. No topographic relationship was found between hippocampal region and thalamic loci for unit suppression. Lemniscal‐type unit responses in ventrobasal thalamus were unaffected by stimulation of the hippocampus or parahippocampal gryus. Interruption of the fornix‐fimbria system prevented suppression elicited from CA1 of DHC, or from CA3 but not FD of VHC. It had no effect on suppression elicited from retrosplenial or entorhinal cortex. Hippocampal regional variation of effectiveness in suppressing extralemniscal pathways may contribute to the differential behavioural involvements reported for different hippocampal structures.
The effect of acetylcholine and dopamine on the caudate spindle in cats
Authors: Keane P. E. , Hall R. C.
Published: January 2005

Electrocortical activity was recorded in cats whose caudate nuclei were perfused and electrically stimulated using a push‐pull cannula. Electric stimulation invariably induced spindles (10—14Hz) in the ipsilateral frontal cortex. Perfusions of acetylcholine together with physostigmine reduced the number of spontaneous spindles, the response to electric stimulation and induced behavioural arousal. This effect was atropine‐sensitive. Perfusions of dopamine with or without tranylcypromine had no significant effect on the number of spontaneous to electric stimulation. Injections of both acetylcholine and dopamine into the cuadate nucleus invariably induced spontaneous spindles and slow waves. The significance of acetylcholine and dopamine in the caudate nucleus initiating caudate spindles and their significance in controlling arousal is discussed.
Nuclear, nucleolar repair, or turnover of dna in adult rat brain
Authors: Wintzerith M. , Wittendorp E. , Rechenmann R. V. , Mandel P.
Published: January 2005

Labeled thymidine administered to adult rats is incorporated at a low level into brain DNA as shown by biochemical and autoradiographic methods. This incorporation takes place in part into neuronal nuclei and nucleoli and also into glial nuclei. While incorporation into glial nuclei is interpreted to represent known glial cell proliferation, incorporation into neuronal nucleoli may be related to nucleolar DNA synthesis, which in turn is responsible for the regulation of nucleolar RNA synthesis. It could also be due to DNA repair synthesis. Assuming this latter phenomenon, our results suggest that nucleolar DNA is more sensitive than chromosomal DNA to ionizing radiations and other factors.
Cyclic 3′, 5′‐nucleotides in extracellular fluids of neural systems
Authors: Cramer Hinrich
Published: January 2005

The cyclic nucleotides (CN) cAMP and cGMP occur in considerable amounts in body fluids such as urine, blood and cerebrospinal fluid (CSF). Whether changes in the CN concentrations of blood and CSF reflect metabolic events within the nervous tissues is a relevant question both in terms of possible roles of CN and of clinical diagnostic purposes. Studies are reviewed which show that cAMP is released from brain slices and from intact peripheral ganglia upon stimulation by electric pulses or exposure to biogenic amines in vitro. By using a prelabeling method with 14C‐adenine evidence is presented that cAMP is released preferentially from a membrane‐associated pool functionally linked to the action of neurotransmitters. In the CSF compartment which is closely related to the extracellular space of the central nervous system, CN levels are in a dynamic equilibrium. An attempt is made to estimate the magnitude of flux rates following inhibition of efflux from the compartment. CN seem to be cleared from the CNS, at least in part, by the choroid plexuses which contain high activities of CN phosphodiesterase but also of adenylate cyclase, possibly related to their secretory and homeostatic functions. Release into and rapid removal from extracellular compartments by transport and degradation may be important means to limit the actions of CN in cells. Whether extracellular CN, in addition, have regulatory functions of their own still remains a matter of speculation.
Spatial propagation of associations in a cortex‐like neural network model
Authors: Wigström Holger
Published: January 2005

A neural network model is studied, having associative memory properties and allowing retrieved associations to propagate within the network. It is intended as a tentative description of the cerebral cortex consisting of “pyramidal cells” with modifiable synapses and “stellate cells” providing feedback through excitatory and inhibitory recurrent pathways.

The model is based on some general assumptions: Learning occurs through facilitation of synapses which depends on simultaneous pre‐ and postsynaptic activity (two‐conditional facilitation). Connections within the network are realizations of a random process, implying that nearby cells are more likely to be connected than distant ones. The two‐conditional facilitation makes it possible for an output signal pattern which occurred in conjunction with a certain input pattern to be retrieved later by reapplying the particular input, the model working as an associative memory. The random connections and the operation of the stellate cell models as linear threshold units give rise to pattern separation in the feedback link. This, in addition to the fact that patterns form associations with themselves, is of importance during the associative recall enabling the network to attain alternative stable modes of activity each corresponding to a learned association.

It is shown that a learned pattern of activity which is retrieved, ie, a stable mode, can propagate across the surface of the network. The mode of activity evoked through a certain association may get into contact with modes originating from different associations, forming a stable or slowly moving boundary between the interacting modes. The model is discussed in relation to some properties of the visual system.