Linked Life Data

2299386

Source:http://linkedlifedata.com/resource/pubmed/id/2299386

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1990-3-6
pubmed:abstractText
1. Intracellular recordings from magnocellular neurons in the supraoptic nucleus (SON) were obtained from rat hypothalamic slices to determine the effects of specific transmitter antagonists on evoked postsynaptic potentials (PSPs), action potential after-discharge, and spontaneously occurring PSPs. 2. Broad-spectrum excitatory amino acid (EAA) antagonists, kynurenic acid (KYN) and gamma-d-glutamylglycine (DGG), significantly diminished or eliminated electrically evoked depolarizing PSPs and spike discharges. These compounds also greatly reduced the amplitude and frequency of spontaneous PSPs. 3. The specific N-methyl-D-aspartate (NMDA) receptor antagonist, DL-2-amino-5-phosphonopentanoic acid (AP5), did not significantly reduce these measures of synaptic activation under these experimental conditions. 4. The gamma-aminobutyric acid (GABA) antagonist, bicuculline methiodide (BIC), partially antagonized some PSPs when the cells were hyperpolarized (-75 to -80 mV) with steady injected currents; KYN antagonized BIC-resistant PSPs. 5. The involvement of a hypothetical cholinergic input to the SON in the responses to stimulation of the region dorsolateral to the SON was tested by bath application of nicotinic cholinergic antagonists, particularly d-tubocurarine (dTC). Nicotinic cholinergic antagonists, even after prolonged exposure to high concentrations, did not block the responses of SON cells to dorsolateral stimulation. 6. These findings strongly suggest that EAAs mediate fast excitatory synaptic responses of SON neurons to stimulation of cells and axons in the region dorsolateral to the SON. The blockade of almost all spontaneous EPSPs by broad-spectrum EAA antagonists likewise argues that EAAs are responsible for the majority of ongoing fast excitatory input. These responses appear to involve an interaction with kainate- and/or quisqualate-type EAA receptors.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
0022-3077
pubmed:author
pubmed:issnType
Print
pubmed:volume
63
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
60-71
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1990
pubmed:articleTitle
Effects of excitatory amino acid antagonists on synaptic responses of supraoptic neurons in slices of rat hypothalamus.
pubmed:affiliation
Department of Physiology, Tulane University School of Medicine, New Orleans, Louisiana 70112.
pubmed:publicationType
Journal Article, In Vitro, Research Support, U.S. Gov't, P.H.S., Research Support, U.S. Gov't, Non-P.H.S.