bluuebunny/crossref_metadata_2025_split huggingface dataset:
The effect of gallamine triethiodide on the activity of gamma motor neurons in the acute spinal cat
Authors: Sherry Clifford J. 
Published: January 2005

AbstractGallamine triethiodide, a drug commonly used in neurophysiological experiments, causes statistically significant and inconsistent changes in the information‐carrying capacity of trains of action potentials generated by members of a population of gamma motor neurons recorded from the same cat under the same conditions during the same time period.
Hepatic enzyme activities in weanling rats with ventromedial and dorsomedial hypothalamic lesions
Authors: Bernardis Lee L. , Rosen Fred , Goldman Jack K. , Martin Roy 
Published: January 2005

AbstractWeanling rats received bilateral electrolytic lesions in the ventromedial (VMN) or dorsomedial (DMN) hypothalamic nuclei; sham‐operated rats served as controls. The animals were maintained under standard conditions for 13–;17 days post‐operatively and killed by decapitation. In addition, to measurements of weight gain and linear growth, Lee Index, and food intake, and activities of several hepatic enzymes and hepatic protein content were determined in untreated rats and in animals injected with 20 mg/kg cortisol 4 hours prior to sacrifice. In accordance with previously established data, weanling rats with VMN lesions did not gain more weight or eat more than their controls but became obese and retarded in linear growth. Weanling rats with DMN lesions showed both reduced ponderal and linear growth and were hypophagic but had normal body composition. Rats with VMN lesions had significantly increased activities of alanine transaminase (AT), serine dehydratase (SD), and hepatic protein; tryptophan oxygenase (TO) was decreased. In VMN‐lesioned rats treatment with cortisol decreased tyrosine aminotransferase (TKT) and liver protein. Lesions in the DMN increased AT and liver protein but left TKT unchanged. Cortisol induced TO and TKT in comparison with vehicle‐treated DMN rats. In another experiment, hepatic alanine tranaminase (AT) and fructose‐1,6,diphophatase (FDPase) were found to be elevated, but levels of pyruvate carboxylase (PC), phosphoenolpyruvate carboxykinase (PEPCK), and plasma glucagon were normal in rats with VMN lesions. The failure to find changes in 2 key gluconeogenic enzymes suggests that the enhanced gluconeogenesis in VMN rats demonstrated in a previous study depends more on substrate availability than on changes in enzyme activity. The data suggest that the central nervous system plays a role in the regulation of certain enzymes involved in protein metabolism.
Free amino acid pool in the brain of mice homozygous for the gene “dilute lethal”
Authors: Simler Dr Simone , Essayag S. , Ledig M. , Koehl C. , Mandel P. 
Published: January 2005

AbstractThe neurologic mutant “dilute lethal” (dl) mice, which reveal several neurologic and biochemical disturbances similar to human phenylketonuria, were used to investigate some aspects of amino acid disorder. We have studied the free amino pool in the brain of “dl” mice and of their control littermates as well as phenylalanine and tyrosine levels in brain and liver as a function of age and after phenylalamine overload. The tyrosine level decreased in brain and liver of affected mice whereas the phenylalanine/tyrosine ratio increased as a function of age. The significantly higher phenylalanine level and phenylalanine/tyrosine ratio in the liver of 20‐day‐old “dl” mice suggest a lower liver phenylalanine hydroxylase activity. After phenylalanine overload, the impairment of phenylalanine metabolism is predominant in the brain of “dl” mice, suggesting a disturbance in phenylalanine hydroxylation. A decrease in the level of several amino acids occurs in the brains of “dl” mice without or after phenylalanine overload; these facts might correspond to a disturbance in the transfer of amino acids to the brain and may lead to impairment in protein synthesis.
Effects of strychnine, bicuculline, and picrotoxin on inhibition of hypoglossal motoneurons
Authors: Felpel Leslie P. 
Published: January 2005

AbstractPostsynaptic potentials, evoked by lingual or hypoglossal nerve stimulation, were recorded from hypoglossal motoneurons of the cat with glass microelectrodes. Lingual nerve‐evoked inhibitory postsynaptic potentials (LIPSPs) were recorded in 98% of hypoglossal motoneurons. Hypoglossal nerve stimulation caused a hyperpolarzing potential following the antidromic spike in all hypoglossal motoneurons tested. This potential was unaffected by depolarizing or hyperpolarizing currents, could not be evoked at a stimulus strength less than that which was threshold for the antidromic action potential, and did not change in shape or amplitude at stimulus strengths which were above threshold for antidromic invasion. This hyperpolarpolarizing potential was therefore considered to be an afterhyperpolarization. However, hypoglossal nerve‐induced inhibitory postsynaptic potentials were recorded from hypoglossal units which had characteristics of interneurons, thus suggesting the presence of afferent fibers in the hypoglossal nerve.The hypoglossal nerve‐induced afterhyperpolarization was not affected by strychnine, bicuculline, or picrotoxin. The LIPSP was antagonized by strychnine but unaffected by bicuculline or picrotoxin. The results suggest that inhibition of hypoglossal motoneurons via the lingual nerve is more likely to be mediated by glycine than gamma‐aminobutyric acid (GABA) and is therefore similar to the strychnine‐sensitive postsynaptic inhibition of spinal motoneurons.
Acetylcholinesterase activity in ventricular and cisternal csf of dogs: Effect of chlorpromazine
Authors: Bareggi Silvio R. , Giacobini Ezio 
Published: January 2005

AbstractAcetylcholinesterase (AChE) activity in dog plasma is significantly higher than in either ventricular or cisternal CSF. However, since protein levels in plasma are about 100‐fold higher than in CSF, the specific activity of AChE is lower in plasma than in CSF. Acetylcholinesterase activity in plasma represents only 22% of total cholinesterase (ChE) activity, while preliminary findings indicate that in ventricular CSF it is 50–60%. Acetylcholinesterase activity in ventricular CSF is significantly lower than in cisternal CSF. Chlorpromazine (10 mg/kg, intravenous), a drug which increases acetylcholine turnover, increased AChE‐specific activity in all dogs. Our results support the hypothesis of a neuronal origin of AChE activity in CSF.
Coding of increments and decrements in stimulus intensity in single units in the cochlear nucleus of the rat
Authors: Møller Aage R. 
Published: January 2005

AbstractThe response of single units in the cochlear nucleus when confronted with step increments and step decrements in stimulus intensity was studied in the rat using tones that were amplitude modulated with square waves or with pseudorandom noise. Cycle histograms of the responses to tones modulated with square waves revealed that the probability of firing increased as a result of step increments in stimulus intensity for tones at characteristic frequency (CF) and that the probability of firing decreased as a result of step decrements. When two tones were presented simultaneously, one at CF and one at the unit's best inhibitory frequency (BIF), and one or the other of the tones was modulated, the modulation of the cycle histogram of the responses was greater than when only one tone was presented. Modulation of the inhibitory tone gave rise to histograms that were mirror images of the histograms of the responses to modulation of the excitatory tone. An increase in probability of firing always occurred at a faster rate than a decrease, independent of whether the increase was brought about by increase in the intensity of the excitatory tone or by a decrease in the intensity of the inhibitory tone.The cycle histograms of the responses to square wave‐modulated tones and the step response estimated from the responses to tones amplitude‐modulated with pseudorandom noise showed a greater similarity when the cycle histograms depicted the case of an increase in the probability of firing than when they concerned a decrease in the probability of firing.
The chemoarchitectonics of the diencephalon of frog (rana tigrina)
Authors: Sood P. P. 
Published: January 2005

AbstractThe study deals with the distribution of acid and alkaline phosphates, ATPase, 5‐nucleotidase, nonspecific esterase, specific cholinesterase, and β‐galactosidase in the diencephalon on the frog.The highlights of the present study are the following: (i) Acid phosphatase is present in all the neurons, whereas the tracts and commissures are completely negative. (ii) Most of the tracts and commissures are positive for 5‐nucleotidase. This confirms the author's previous findings that the tracts and commissures of all the areas of frog brain are intensely positive for 5‐nucleotidase. (iii) β‐galactosidase activity in the nuclei of the diencephalon is either mild or completely absent, whereas the commissures and tracts show positive activity. (iv) Habenulothalamic connections are intensely positive for specific cholinesterase and non‐specific esterase, moderately positive for β‐galactosidase and completely negative for other enzymes. (v) The epiphysis (pineal organ) shows intense reaction for adenosine triphosphatase, acid phosphatase, and 5‐nucleotidase and moderate reaction for alkaline phosphatase and non‐specific esterase. In contrast to the above enzymes, the specific cholinesterase and β‐galactosidase are completely missing. (vi) Lateral forebrain bundles are completely negative for all the enzymes except alkaline phosphatase and β‐galactosidase.The distribution of these enzymes has been correlated with the functional aspects of various nuclei, tracts, and commissures of the diencephalon of the frog.
Intracellular studies of GABA and taurine action on the neurons of the cat sensorimotor cortex
Authors: Alexandrov A. A. , Batuev A. S. 
Published: January 2005

AbstractThe action of taurine and GABA on the cat cerebral cortex neurons was studied. Electrophoretically administered taurine and GABA hyperpolarized the neuron membrane. GABA, in contrast to taurine, sharply increased the somatic membrane conductance. Taurine action was weaker than that of GABA and its effects were not always observed. However, in a number of instances it exerted inhibitory influence similar to GABA action. Some facts make it possible to suppose that taurine acts mainly on the neuron dendrites. The data obtained are in accordance with the supposition that taurine might be an inhibitory transmitter in the cerebral cortex.
Cystathionine synthase in rat brain: Regional and time‐of‐day differences and their metabolic implications
Authors: Lee Kohl Randall , Quay W. B. 
Published: January 2005

AbstractIn relation to concern for probable interrelations of cystathionine synthase (CS, EC 4.2.1.21) and methionine, one‐carbon, and 5‐hydroxytryptamine metabolism, we have investigated tissue and time‐of‐day differences in CS activity in the laboratory rat under standardized conditions. Liver, kidney, and pancreas had highest CS activities; nine regions of the CNS had mean activities ranging from 4.5% (lumbosacral cord) to 24.5% (hypothalamus) of mean hepatic activity; pituitary and adrenal glands lacked detectable CS activity. Although significantly lower CS activity occurred in liver (↓ 9%, P < 0.050) and kidney (↓ 13%, P < 0.025) during the interval two hours before to two hours after the daily onset of darkness, no significant changes were found in hypothalamus, cerebellum, or medulla oblongata. Regional CNS differences in CS activity appeared to be without correlation in relation to published data on relative contents of 5‐hydroxytryptamine, tryptophan 5‐hydroxylase (EC 1.14.16.4), 5,10‐methylene reductase N5‐methyltetrahydrofolate‐NAD‐oxidoreductase, (EC 1.1.1.78), or 5‐methyltetrahydrofolate. Therefore, among CNS regions examined, a critical deficiency in ability to metabolize a homocysteine load is considered to be unlikely under normal conditions.
Dissociated effects of inhibition of catecholamine synthesis on motor activity, “emotionality,” and aggression in mice
Authors: Matte A. C. , Tornow H. 
Published: January 2005

AbstractThe inhibitor of catecholamine synthesis at the tyrosine hydroxylase level, alpha‐methyltyrosine, administered in daily doses of 250 mg/kg IP, altered motor activity and aggressive behavior of isolated male mice in ten‐minute paired encounter tests conducted on nine successive days. Motor activity was determined by an electromagnetic activity meter which measures fine and coarse movements separately. Coarse motor activity correlated significantly with aggressive behavior. Nonagressive fine motor activity was significantly increased, while all the parameters of aggressive behavior showed a significant decrease in aggression. Increased escape behavior, heterogrooming, squeaking, and two cases of stupor were observed, suggesting possible equivalents of anxiousness. The defecation rate did not differ from that of the control group, victors having had a higher rate than losers.Results are discussed in connection with the “construct of emotionality” and the hypothesis of there being several categories of aggression with corresponding biochemical correlations.
High‐energy phosphate compounds and some glycolytic substrates in the rat brain during hypoxia
Authors: Broniszewska‐Ardelt Barbara , Sikorska Marianna 
Published: January 2005

AbstractThe influence of acute and prolonged (with resuscitation) hypoxia, upon some glycolytic substrates and high energy phosphate compounds in the rat brain, was studied. Acute hypoxia decreased the content of glucose and glucose‐6‐phosphate as well as of high energy phosphate compounds. Simultaneously, an increase of lactic acid level was recorded.Some adaptation features could be observed, when 30‐minute hypoxia with resuscitation was studied. Brain content of high energy compounds returned to the normal value, while that of glucose increased twice over control. However, the level of lactic acid was still increased.
Hypothalamic cathepsin D: Assay and isoenzyme composition
Authors: Akopyan T. N. , Barchudaryan N. A. , Karabashyan L. V. , Arutunyan A. A. , Lajtha A. , Galoyan A. A. 
Published: January 2005

AbstractA sensitive and convenient method of endopeptidase assay using as substrate globin modified with pyridoxal‐5‐phosphate was used for determination of acid proteinases in bovine hypothalamus separated by isoelectric focusing. The soluble protein fraction of hypothalamus upon elution from Sephadex gave five peaks of proteinase activity at pH 3.2. The properties indicate that these peaks of endopeptidase activity are isoenzyme forms of cathepsin D.
Metabolic inhibitors and subcellular distribution of GABA
Authors: Sarhan Shakir , Seiler Nikolaus 
Published: January 2005

AbstractExperimental procedures are described which are believed to yield results that reflect, within certain limits, the in vivo changes of the size of the GABA pool in nerve endings in comparison with those of all other GABA pools. Two irreversible GABA‐T inhibitors, vinyl GABA and acetylenic GABA, two GAD inhibitors, 3‐mercaptopropionic acid and pyridoxal phosphate glutamyl‐γ‐hydrazone, and di‐n propylacetate, a clinically useful anticonvulsant, have been studied to determine their effects on GABA compartmentalization in mouse brain cortex.The changes elicited by these drugs in subcellular fractions of brain cortex homogenates support the notion that measurement of amino acid concentrations in crude synaptosomal fractions and in supernatant fractions under controlled conditions allow one to draw conclusions about relative changes of pool sizes in vivo. In particular this work showed that a specific increase in the concentration of GABA within the nerve endings is more important than a large increase of total brain GABA as a means of decreasing susceptibility to a variety of chemically or physically induced seizures.
On some derivatives of ferrocene, novel acetylcholinesterase inhibitors
Authors: Hetnarski Bogumil , Lajtha Abel , Wisniewski Henryk M. 
Published: January 2005

AbstractEight novel methylcarbamates, derivatives of ferrocenylketoximes and aldoximes, and ferrocenyl‐p‐hydroxyphenylaldimine were prepared. They are the first carbamates in the field of ferrocene derivaties. Their anticholinesterase activity was tested and found to fall in the range of 10−4 through 10−6 M (I50). The correlation between the activity of the compounds and the kind of substitutents grafted on the methylene carbon atom is discussed.
The role of the medial septal nucleus in mediating adrenocortical responses to somatosensory stimulation
Authors: Feldman Shaul , Conforti Nissim 
Published: January 2005

AbstractIn view of the demonstrated involvement of the hippocampus in the mediation of adrenocortical responses following sciatic nerve stimulation, the role of the septum and the preoptic area in the transmission of this response was investigated. Changes in plasma corticosterone following ether stress and photic, acoustic, or sciatic nerve stimulation were studied in intact rats and in animals with lesions in the medial septal nucleus and the preoptic area. The response to ether stress and to photic and acoustic stimulation was normal in these animals. However, the adrenocortical response to sciatic nerve stimulation was partially reduced in the rats with lesions in the superior, but not in the inferior preoptic area, and it was completely blocked in those with medial septal lesions. Our previous and present experiments indicate that the ventral hippocampus, the fimbria, the septum, and anterior hypothalamic afferents mediate the adrenocortical response to somatosensory stimulation.
Choline acetyltransferase: Purification and characterization
Authors: Chao Li‐Pen 
Published: January 2005

AbstractCholine acetyltransferase catalyzes the synthesis of the neurotransmitter acetylcholine and is the specific enzyme marker for cholinergic neurons. This review summarizes and discusses different purification procedures, as well as the characteristics of this important enzyme. Explanations for conflicting or controversial results concerning this enzyme are also discussed.
Increased activity of a phospholipid base‐exchange system by the differentiation of neoplastic cells from the nervous system
Authors: Erkell L. J. , de Medio G. E. , Haglid K. , Porcellati G. 
Published: January 2005

AbstractThe activity of a base‐exchange enzyme system, specific for the polar headgroups of brain phospholipids, was measured in both C 1300 mouse neuroblastoma (clone 41 A3) and human glioma 138 MG cell lines. This base‐exchange is thought to occur between free nitrogenous bases and membrane‐bound phospholipids. The incorporation of free 14C‐labeled ethanolamine and L‐serine was determined in undifferentiated and morphologically differentiated cells. Both cell lines showed a significant increase in ethanolamine and L‐serine incorporation upon differentiation.
Dextro‐phenylalanine inhibits potassium‐evoked 3H‐noradrenaline release from hypothalamus but not of 3H‐dopamine from rat caudate nucleus
Authors: Julio Pardal Fernández 
Published: January 2005

AbstractAction of dextro‐phenylalanine (d‐Phe) on catecholamine release elicited by K+ 20 mM has been studied in isolated slices of rat central nervous system (CNS). d‐Phe (3 × 10−3 M) produced inhibition of the fractional release of 3H‐noradrenaline but not of 3H‐dopamine. The mentioned effect is Ca2+ dependent and was antagonized when this ion was incremented to 2.6 mM in the medium or in the presence of ionophore A‐23187 (4 × 10−5 M). Neither acetylsalicylic acid nor indomethacin (prostaglandin biosynthesis inhibitors) interferes with the effect of d‐Phe, showing that by itself it would not reach through the prostaglandin pathway. d‐Phe modified neither the noradrenaline neuronal uptake nor its metabolism at the CNS. The findings suggest that d‐Phe acts through a Ca2+‐dependent mechanism, possibly by specific receptors and in parallel with feedback circuits that involve alpha‐adrenoceptors, muscarinic receptors, or prostaglandins.
Starvation‐induced changes in transport of ketone bodies across the blood‐brain barrier
Authors: Pollay Michael , Alan Stevens F. 
Published: January 2005

AbstractThe permeability of the blood brain barrier (BBB) to β‐hydroxybutyrate (β‐HB) was computed in fed and starved (five days) rats by the simultaneous measurement of cerebral blood flow (diffusible indicator method‐123I‐iodoantipyrine) and brain uptake of 14C‐β‐HB (relative to a 3H2O reference). The results from the present study demonstrate that the movement of β‐HB across the BBB in rat is by a carrier‐mediated process. During starvation, total movement (carrier‐mediated and diffusionary) of this ketone body into brain was observed to be enhanced because of an increase in the diffusionary loss across the cerebral capillary. The calculated transport kinetics also suggest that the β‐HB molecule has a greater affinity for the transport (mediator) protein during starvation, although the maximal rate of uptake by brain due to a carrier processes mediated Vmax is decreased either because there is a smaller quantity of the mediating molecule or because there is trans inhibition by a high cellular concentration of β‐HB or some analog.
Effects of 2‐deoxy‐D‐glucose on multi‐unit activity of the hypothalamus in rats
Authors: Rabin Bernard M. , Miller Donald S. 
Published: January 2005

AbstractMutli‐unit activity was recorded from the diencephalon of unanesthetized, immobilized female rats. Less than 50% of the recording sites in the hypothalamus showed changes in the level of multi‐unit activity to changes in the level of glucose utilization induced by injection of 2‐deoxy‐D‐glucose (2‐DG). It was also not possible to specificy an area within the hypothalamus in which there was a concentration of recording sites which consistently responded to 2‐DG. Relatively large amplitude, long duration changes in multi‐unit activity levels were also observed in the optic tract, suggesting that 2‐DG induced a widespread cellular metabolic response to glucoprivation which may not have been related to the regulation of feeding.
DNA DNases in normal and undernourished rat brain
Authors: Rao K. Subba , Shrivastaw K. P. , Tiwari B. K. 
Published: January 2005

AbstractEarlier studies from our laboratory [Shrivastaw and Subba Rao, 1975; Subba Rao and Shrivastaw, 1976] have indicated a positive correlation between cell proliferation, as indicated by DNA synthesis, and the levels of DNases in developing chick brain. Since undernutrition is known to affect cell prolifereration in developing brain, those studies are now extended to see the effect of early undernutrition on the levels of DNA and DNases along with RNA and protein in developing rat brain. Early nutritional deprivation resulted in lesser amounts of DNA, but the concentration of DNA per gram of brain did not alter. DNA, RNA, and protein values in brains of those rats undernourished from birth to 14 days but subsequently rehabilitated up to 130 days, exhibuited complete recovery, while rehabilitation up to 50 days did not show full recovery in the case of DNA. Both the specific activity and total activity of acid and alkaline DNases showed significant reduction in 14‐day‐old undernourished brain. However, with continued nutritional restriction up to 24 days, the specific activity of these enzymes returned to normal, although the total activity was still in deficit. These results, coupled with those on DNA levels, indicate that a compensatory mechanism may come into play when developing brain is exposed to caloric restriction.