bluuebunny/crossref_metadata_2025_split huggingface dataset:
Development of inhibitory and excitatory synaptic transmission in the rat dentate gyrus
Authors: DiScenna Pascal G. , Teyler Timothy J. 
Published: May 2005

AbstractWe studied the ontogeny of inhibitory and excitatory processes in the rat dentate gyrus by examining paired‐pulse plasticity in the hippocampal slice preparation. The mature dentate gyrus produces characteristic paired‐pulse responses across a wide range of interpulse intervals (IPI). Paired‐pulse effects on population excitatory postsynaptic potential (EPSP) slope and population spike (PS) amplitude were analyzed at postnatal day 6 (PN6), PN7/8, PN9/10, PN15/16, and PN > 60.The synaptic paired‐pulse profile (10–5,000 ms IPI) matured by PN7/8. The triphasic pattern of short‐latency depression, a relative facilitation at intermediate intervals, and long‐latency depression was present at all ages tested. Paired‐pulse effects on granule cell discharge indicated the presence of weak short‐latency (20 ms IPI) inhibition at PN6, the earliest day that a population spike could be evoked. By PN7/8, short‐latency inhibition was statistically equivalent to the mature dentate gyrus. Long‐latency (500–2,000 ms IPI) PS inhibition was present, and equal to the mature dentate gyrus by PN6. The most consistent difference between the mature and developing dentate gyrus occurred at intermediate IPIs (40–120 ms) where spike facilitation was significantly depressed in the developmental groups.The studies indicate that short‐term plasticity matures rapidly in the dentate gyrus and suggest that the inhibitory circuitry can function at a surprisingly early age. © 1994 Wiley‐Liss, Inc.
Ultrastructural plasticity of the dentate gyrus granule cells following recurrent limbic seizures: II. Alterations in somatic synapses
Authors: Bundman Marsha C. , Gall Christine M. 
Published: May 2005

AbstractHilus lesion‐induced recurrent limbic seizures cause a dramatic increase in the numbers of somatic spines on dentate gyrus granule cells in the adult rat. Somatic spines are maximally increased 3 h after the initiation of seizures at which time many of these spines form synapses. The present quantitative electron microscopic study assessed the numbers and types of synapses present on the granule cell perikarya and somatic spines of control and experimental seizure rats with the goal of determining if newly elaborated somatic spines arise at the site of pre‐existing synapses or are associated with new innervation. Experimental rats were sacrificed 5 h after hilar lesion placement (or 3 h after seizure onset). In both control and hilus‐lesioned (HL) rats, 15–20% of the somatic spines could be seen to form synaptic contacts within a single plane of section; these synapses were almost exclusively of the asymmetric type. With the increased incidence of spines in experimental‐seizure rats, there was a 6.25‐fold greater number of spine synapses in HL versus control rats. There was, in addition, a 60% decrease in the number of asymmetric synapses occurring directly on the granule cell perikarya but no change in the total (spine plus somatic) number of asymmeteric synapses. Although few asymmetric synapses were associated with spines in control tissue, 60–70% of asymmetric synapses were associated with spines in experimental‐seizure tissue. In addition, in hilus lesion rats symmetric somatic synapses were increased by 20% on cells in deep stratum granulosum resulting in a dissolution of the superficial‐to‐deep innervation gradient present in the untreated rat. These findiings support the conclusion that spines induced by seizure activity form at the site of pre‐existing asymmetric synapses on the granule cells and demonstrate that brief seizure episodes can rapidly induce marked changes in innervation patterns in the adult brain. © 1994 Wiley‐Liss, Inc.
NADPH diaphorase‐positive neurons in the lizard hippocampus: A distinct subpopulation of GABAergic interneurons
Authors: Dávila José C. , Megías Manuel , Andreu Manuel J. , Real María A. , Guirado Salvador 
Published: May 2005

AbstractWe analyzed the distribution and light‐microscopic features of the NADPH diaphorase‐containing structures in the lizard hippocampus, likely to correspond to nitric oxide. We also studied co‐localization of NADPH diaphorase with the neurotransmitter GABA, the calcium‐binding protein parvalbumin, and the neuropeptide somatostatin, in order to examine whether putative nitric oxide‐synthesizing neurons represent a different subpopulation of GABA cells, on which the authors recently reported in lizards. We also studied co‐localization of NADPH diaphorase with parvalbumin or somatostatin in mice to ascertain whether the characteristics of this population in reptiles parallel the situation in mammals. Most of the positive NADPH diaphorase neurons were stained in a Golgi‐like manner and were in the plexiform layers of the lizard hippocampus with morphologies ranging from bipolar to multipolar. Co‐localization with GABA was 100%, and NADPH diaphorase‐positive neurons in the lizard hippocampus did not contain parvalbumin or somatostatin. The results indicate that putative nitric oxide‐synthesizing neurons represent a distinct subpopulation of GABA interneurons in the lizard hippocampus. Two different types of fibers were described in the plexiform layers: one type bearing thick varicosities, and the other thinner ones. We discuss the possibility that at least part of the positive fibers arise from a hypothalamic aminergic nucleus containing the third ventricle, the periventricular hypothalamic organ. Most radial glia were stained almost completely and formed typical end‐feet both at the pia and around capillaries. The results of this study confirm that the capacity for synthesizing nitric oxide is linked to a determined set of neuronal markers depending on the specific brain region, and they provide new resemblances between hippocampal regions in different classes of vertebrates. © 1995 Wiley‐Liss, Inc.
Configural association theory and the hippocampal formation: An appraisal and reconfiguration
Authors: Rudy Jerry W. , Sutherland Robert J. 
Published: May 2005

AbstractSutherland and Rudy ([1989] Psychobiology 17:129–144) proposed that the hippocampal system is critical to normal learning and memory because of its function as the central part of a configural association system. This system constructs a unique representation of the joint occurrence of the independent elements of a compund. There is evidence consistent with the theory's predictions, however, there also are data that unambiguously demonstrate that, under some conditions, animals lacking an intact hippocampal system acquire configural associations. Thus, Sutherland and Rudy's fundamental assumption cannot be correct. To integrate the supporting and contradictory data, we propose two simple modifications of our position: (1) The critical neural system for configural associations is in cortical circuitry outside the hippocampus, and (2) the output from the hippocampal formation contributes to configural processing by selectively enhancing, thereby making more salient, cortical units representing stimulus conjunctions. This enhancement has two important effects: (1) It decreases the similarity between the configural units representing the co‐occurrence of cues and the units representing the cues, and (2) it increases the rate at which the configural units can acquire associative strength. The modified theory explains why damage to the hippocampal formation only impairs learning on a subset of nonlinear discrimination problems. It also integrates recent data on the effects of hippocampal formation damage on conditioning involving context cues and makes novel predictions about performance on nonlinear discrimination problems and place learning. © 1995 Wiley‐Liss, Inc.
View‐responsive neurons in the primate hippocampal complex
Authors: Rolls Edmund T. , O'Mara Shane M. 
Published: May 2005

AbstractRecordings were made from single neurons in the hippocampus and parahippocampal gyrus while macaques were moved on a platform mounted on a free‐moving robot or on wheels in a cue‐controlled 2 m × 2 m × 2 m environment, in order to investigate the representation of space and of spatial memory in the primate hippocampus. The test conditions allowed factors that might account for spatial firing of the cells, including the spatial location where the monkey looked, the place were the monkey was, and the head direction of the monkey, to be identified. The responses of some (“view”) neurons depended on where the monkey was looking in the enviornment, but not on the place of the monkey in the environment. The responses of one other neuron depended on a combination of where the monkey was facing and his place in the test chamber. The response of view‐dependent neurons was affected by occlusion of the visual field. It was possible to show for one neuron that its “view” response rotated with rotation of the test chamber. Some neurons responded to a combination of whole‐body motion and view or place, and one neuron responded in relation to whole‐body movement to a particular place. One neuron responded depending on the place where the monkey was in the environment and relatively independently of view.The representations of space provided by hippocampal view‐responsive neurons may be useful in forming memories of spatial environments (for example, of where an object has been seen and of where the monkey is as defined by seen views) and, together with whole‐body motion cells, in remembering trajectories through environments, which is of use, for example, in short range spatial navigation. © 1995 Wiley‐Liss, Inc.
Quantitative morphological analysis of subicular terminals in the rat entorhinal cortex
Authors: van Haeften Theo , Jorritsma‐Byham Barbara , Witter Menno P. 
Published: May 2005

AbstractIn the present report, we describe a morphological and quantitative analysis of subicular synapses in layer V of the lateral entorhinal cortex (LEA) of the rat. Projections from the dorsal subiculum were labeled anterogradely, and areas in LEA showing high terminal density were randomly selected for ultrathin sectioning. More than 400 terminals in LEA were photographed in the electron microscope, and synapse types and postsynaptic targets were identified and, subsequently, quantified with the unbiased disector method. Most subicular terminals appeared to form asymmetrical synapses. A majority of asymmetrical synapses terminated on spines (67.5%), whereas a smaller fraction of asymmetrical synapses (23.5%) terminated on dendritic shafts. A small fraction of the terminals (7%) had symmetrical features. These symmetrical synapses had an almost equal percentage of spines and dendritic shafts as postsynaptic elements. Labeled synapses on somata or axons were never observed. The findings of this study in conjunction with relevant electrophysiological observations (Jones [1987] Neurosci Lett 81:209–214) leads to the conclusion that the subiculo‐entorhinal pathway comprises a large excitatory and a smaller inhibitory projection, both making synaptic contacts with presumed principal neurons and interneurons in the entorhinal cortex. © 1995 Wiley‐Liss, Inc.
L‐Tryptophan and prolactin release: Evidence for interaction between 5‐HT1 and 5‐HT2 receptors
Authors: Charig E. M. , Anderson I. M. , Robinson Sen J. M. , Nutt D. J. , Cowen P. J. 
Published: May 2005

AbstractThe effects of the selective 5‐HT2 receptor antagonist, ritanserin, on the growth hormone (GH) and prolactin (PRL) responses to intravenous L‐tryptophan (LTP) were assessed in 8 normal volunteers. Administration of ritanserin (40 mg orally) prior to infusion of LTP (5 g) significantly enhanced the PRL responses but not those of GH. The results are consistent with previous proposals that the endocrine responses to LTP are mediated by 5‐HT1 rather than 5‐HT2 receptors and also suggest that 5‐HT2 receptor antagonists may increase certain 5‐HT1 mediated responses in the human brain.
High levels of tyramine in some Chinese foodstuffs
Authors: Sung S. K. , Lee C. M. , Young J. D. , Chen C. N. 
Published: May 2005

AbstractThere are many reports regarding the risk of hypertensive crisis when tyramine‐containing food is taken together with monoamine oxidase inhibitors (MAOIs). Thus, psychiatric patients taking MAOIs are routinely given dietary warning cards. However, most of these cards have been prepared according to assays of tyramine in Western food samples. We now report the detection of high levels of tyramine (ranging from 0.02 to 43.0 μmol/g) in some common Chinese foods, including fermented bean curd, soy sauce and fermented soya bean.
The lack of CNS effects of nizatidine, with and without alcohol, on psychomotor ability and cognitive function
Authors: Hindmarch I. , Gilburt S. 
Published: May 2005

AbstractThe aim of the study was to measure the effects of nizatidine (150 mg, 300 mg, and 600 mg), with and without alcohol (0.5 g/kg body weight) on a battery of test of psychomotor functioning, short‐term memory and subjective rating of sedation. A placebo and positive internal control (lorazepam 1 mg) crossover design was used, with each subject acting as her own control. The study population consisted of 10 healthy female volunteers with an age range of 20–50 years. The results show that nitatidine, at the range of doses studied, has no demonstrable effect on any of the measures of CNS activity and psychomotor performance. This lack of CNS effect was demonstrated in a study where the verum showed a consistent impairment of CNS activity. Furthermore there was no potentiation of the effects of alcohol by any of the doses of nizatidine used.
Some factors related to the use of psychoactive drugs, in an institution for adults with mental handicap
Authors: Harlow P. , Morton S. , Wright E. 
Published: May 2005

AbstractA 1‐day audit (on 11 March 1985) of the psychotropic drugs prescribed for 1084 institutionalized adults with mental handicap in a long‐stay hospital is reported. The relevance of staffing levels, chronological age, sex and mental level is considered. Of the 1084 patients, 35 per cent were 17–44 years old and 65 per cent were 45 years or older; 51 per cent were severely and 40 per cent were profoundly mentally retarded; 23 per cent received antiepileptic drugs; 22 per cent received antipsychotic drugs. The hospital's nurse:patient ratio was nationally recognized as among the worst in England. There was no evidence that a low staffing level was associated with a high level of antipsychotic drug use, but there was an inverse relationship to age, and to mental level. Significantly more women than men received antipsychotics/anxiolytics, antidepressants or hypnotics/sedatives.
The comparative cognitive side‐effects of lithium, carbamazepine and combined lithium‐‐carbamazepine in patients treated for affective disorders
Authors: Andrewes D. G. , Schweitzer I. , Marshall N. 
Published: May 2005

AbstractThe cognitive side‐effects of lithium, carbamazepine (CBZ) and combination CBZ and lithium were compared in a crossover double‐blind study. The CBZ range was 17–26 Mmol/1 and the lithium range 0·41–1·10 mmol/1. Twelve subjects (seven females, five males), five with bipolar and seven with unipolar affective disorders, were randomly distributed to one of three group; the order of the conditions was different for each group, whereby each condition was tested in each of the three time phases of the study. The group varied according to the order of the three drug conditions. From measures of memory, attention and perceptuomotor functioning two measures showed significant differences between drug conditions. A tracking task showed impairment in the combined CBZ‐‐lithium condition compared to the single administration of either drug. A memory task testing cued recall for prose was performed better in the CBZ group; results were not confounded by correlations with self‐ratings of mood.
Computer‐analysed EEG and psychometric assessment of two new non‐benzodiazepine tranquillizers in healthy volunteers
Authors: Patat A. , Klen M. J. , Hucher M. , Granier J. 
Published: May 2005

AbstractThe effects on CEEG, psychomotor performance and attention of diazepam 10 mg, RU 43028 100 mg, RU 32698 100 mg and placebo administered orally have been investigated in 12 healthy subjects in a double‐blind controlled study. The effects of the compounds were evaluated by objective tests (CEEG, measurement of body sway, critical flicker fusion, visual reaction time, tapping test, arithmetical calculation) and subjective measurements (visual analogue scales and side‐effects questionnaire). Measurements were taken before treatment and after 30 min, 2 h, 3.5 h and 6.5 h. Placebo and RU 43028 did not affect any of the tests used. Diazepam induced an increase in beta rhythms and a decrease in theta and alpha rhythms on CEEG. These expected patterns were correlated with plasma concentrations. It also induced sedative side‐effects characterized by an increase of body sway and reaction time and a decrease of CFF and arithmetical calculation. RU 32698 displayed on atypical profile on CEEG with a reduction of alpha and theta rhythms without changes in beta and delta rhythms. It did not have any psychometric incapacitating effect.
The effects of diazepam on cognitive processing
Authors: Golombok S. , Mathews A. , Macleod C. , Lader M. 
Published: May 2005

AbstractThe study was designed to investigate the effects of diazepam on cognitive processing, and in particular to look at whether or not the drug reduces the bias towards the processing of threatening information shown by anxious subjects. Forty anxious female subjects were randomly and blindly allocated to two treatment groups; 10 mg diazepam or a placebo. Each subject was tested before and after treatment on a colour‐naming task designed to measure selective attention towards both stressor‐related and generally threatening material. It was found that the subjects showed a cognitive bias favouring the processing of threatening information, but that diazepam did not reduce this interference effect. This suggests that diazepam does not have a direct effect on cognitive aspects of anxiety.
Effects of an alpha‐2 adrenoceptor antagonist, Org 3770, upon the autonomic function of the pupil
Authors: Palazidou E. , Sitsen J. M. A. , Checkley S. A. 
Published: May 2005

AbstractThe effects of a single oral dose of an alpha‐2 adrenoceptor antagonist, Org 3770 (30 mg), upon the autonomic function of the human pupil have been investigated in six volunteers. Org 3770 reduced pupil diameter, possibly as a result of its alpha‐2 adrenoceptor blocking activity. Org 3770 did not reduce the mydriatric effect of phenylephrine and tyramine, nor was the miotic response to pilocarpine affected. These results are consistent with a blockade by Org 3770 of central alpha‐2 adrenoceptors.
Study of the potential pharmacodynamic antagonism of RU 41 656 on scopolamine and triazolam impairment in healthy subjects
Authors: Patat A. , Klein M. J. , Surjus A. , Hucher M. , Granier J. 
Published: May 2005

AbstractThe potential improvement on attention and memory of a single oral does of RU 41 656, and the potential antagonism of the deficits of these functions induced by oral administration of scopolamine 1 mg and triazolam 0.5 mg, have been investigated in a six‐period, placebo‐controlled, double‐blind, crossover study involving 12 healthy young volunteers. The effects of the compounds were evaluated by objective test (Buschke selective reminding test, CFF, simple and multiple‐choice reaction time, tapping, arithmetical calculation, DSST) and subjective measurements (visual analogue scale, side‐effects questionnaire). Measurements were taken before treatment and 2, 4 and 7h after RU 41 656 intake. Neither placebo alone nor RU 41 656 alone modified the performances of these subjects. Under the experimental conditions of the trial, scopolamine given orally did not cause the disturbances of attention and memory usually described. On the contrary, triazolam caused a pronounced impairment of vigilance and memory. RU 41 656 did not antagonize the sedative effects of triazolam, but partially attenuated its amnesic effects.
Antidepressants and memory: A review
Authors: Thompson P. J. 
Published: May 2005

AbstractAntidepressant medications have been in general use since the late 1950s. Many patients are treated as outpatients and often continue with their normal routines during treatment. Individuals may undertake activities where any change in memory functioning, negative or positive, might have important consequences. Furthermore, many antidepressants have similar efficacy. Information about differential effects upon memory would seem valuable information for the clinician to have at his or her disposal. This paper reviews available evidence on the effects of antidepressants on human memory. Many studies have involved the single or short‐term administration of antidepressants to healthy volunteers, thereby not acknowledging that depression per se has a negative impact on memory processes. Even in the studies on patient samples, groups very with regard to type and severity of depression, dosage and duration of treatment. Limited evidence, however, does suggest that antidepressants may exert differential effects upon memory functioning which could be predicted from their action on specific neurotransmitter system.
Performance tests in human psychopharmacology (2): Content validity, criterion validity, and face validity
Authors: Parrott A. C. 
Published: May 2005

AbstractThe four traditional aspects of validity comprise: criterion, content, face and construct. Criterion validity is assessed by calculating the degree of correlation between test score and external criterion (e.g. driving ability of flying skill). While this form of evidence is rare, it has been demonstrated in a few psychopharmacology studies, especially with psychomotor tasks (e.g. target tracking). Content validity is an index of the appropriateness of test selection. Many test batteries cover a wide range of psychological functions, and thus display a degree of content validity. However, the functions being assessed often differ, reflecting the absence of agreement over what ‘human performance’ should comprise. Most test batteries also contain a preponderance of simple tasks, and content validity could be improved through the inclusion of ‘higher cognitive’ tasks. The difficulties of assessing performance using a single test are also critically examined. Face validity is not a true index of validity, but a reflection of whether the test looks right. It can often be misleading, although it does have positive functions (e.g. for subject motivation). Sensitivity to psychoactive drug effect is also a prerequisite for tests in this area, although it is not in itself an index of validity. The construct validity of human performance tests, together with an overview of test meaning and interpretation, are examined in the final paper of this series.
ECT‐induced prolactin release: Effect of sex, electrode placement and serotonin uptake inhibition
Authors: Zis A. P. , Goumeniouk A. D. , Clark C. M. , Grant B. E. K. , Remick R. A. , Lam R. W. , Garland E. J. 
Published: May 2005

AbstractWe and others have previously reported that the non‐specific serotonin receptor antagonist methysergide inhibits the PRL response to ECT wheras the 5HT‐2 antagonists ketanserin and ritanserin have no effect. In the present study the effect of serotonin uptake inhibition on this neuroendocrine response was examined in two separate placebo‐controlled experiments. According to our results neither clomipramine (25 mg orally) nor fluoxetine (20 mg orally) affected the PRL response to ECT. An analysis of the placebo day data from 32 subjects indicates that a high PRL response to ECT is associated with female sex and bilateral electrode placement.