Linked Life Data

10669486

Source:http://linkedlifedata.com/resource/pubmed/id/10669486

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
2000-4-7
pubmed:abstractText
This investigation used an in vitro hypothalamic brain slice preparation and whole cell and perforated-patch recording to examine the response of magnocellular neurons in hypothalamic paraventricular nucleus (PVN) to bath applications of vasopressin (VP; 100-500 nM). In 22/38 cells, responses were characterized by an increase in the frequency of bicuculline-sensitive inhibitory postsynaptic potentials or currents with no detectable influence on excitatory postsynaptic events. Perforated-patch recordings confirmed that VP did not have an effect on intrinsic membrane properties of magnocellular PVN neurons (n = 17). Analysis of intrinsic membrane properties obtained with perforated-patch recording (n = 23) demonstrated that all of nine VP-sensitive neurons showed a rebound depolarization after transient membrane hyperpolarization from rest. By contrast, 12/14 nonresponding neurons displayed a delayed return to resting membrane potentials. Recordings of reversed inhibitory postsynaptic currents with chloride-loaded electrodes showed that responses to VP persisted in media containing glutamate receptor antagonists but were abolished in the presence of tetrodotoxin. In addition, responses were mimicked by vasotocin [Phe(2), Orn(8)], a selective V(1a) receptor agonist, and blocked by [beta-Mercapto-beta, beta-cyclopentamethylenepropionyl(1),O-Me-Tyr(2), Arg(8)]-VP (Manning compound), a V(1a)/OT receptor antagonist. Neither [deamino-Cys(1),Val(4),D-Arg(8)]-VP, a selective V(2) receptor agonist, nor oxytocin were effective. Collectively, the results imply that VP acts at V(1a) receptors to excite GABAergic neurons that are presynaptic to a population of magnocellular PVN neurons the identity of which features a unique rebound depolarization. Endogenous sources of VP may be VP-synthesizing neurons in suprachiasmatic nucleus, known to project toward the perinuclear regions of PVN, and/or the magnocellular neurons within PVN.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
0022-3077
pubmed:author
pubmed:issnType
Print
pubmed:volume
83
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
705-11
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed-meshheading:10669486-Action Potentials, pubmed-meshheading:10669486-Animals, pubmed-meshheading:10669486-Bicuculline, pubmed-meshheading:10669486-Electric Stimulation, pubmed-meshheading:10669486-Excitatory Amino Acid Antagonists, pubmed-meshheading:10669486-GABA Antagonists, pubmed-meshheading:10669486-Interneurons, pubmed-meshheading:10669486-Male, pubmed-meshheading:10669486-Neural Inhibition, pubmed-meshheading:10669486-Oxytocin, pubmed-meshheading:10669486-Paraventricular Hypothalamic Nucleus, pubmed-meshheading:10669486-Patch-Clamp Techniques, pubmed-meshheading:10669486-Quinoxalines, pubmed-meshheading:10669486-Rats, pubmed-meshheading:10669486-Rats, Long-Evans, pubmed-meshheading:10669486-Receptors, GABA-A, pubmed-meshheading:10669486-Synaptic Transmission, pubmed-meshheading:10669486-Tetrodotoxin, pubmed-meshheading:10669486-Vasoconstrictor Agents, pubmed-meshheading:10669486-Vasopressins, pubmed-meshheading:10669486-gamma-Aminobutyric Acid
pubmed:year
2000
pubmed:articleTitle
Vasopressin increases GABAergic inhibition of rat hypothalamic paraventricular nucleus neurons in vitro.
pubmed:affiliation
Netherlands Institute for Brain Research, 1105 AZ Amsterdam, The Netherlands.
pubmed:publicationType
Journal Article, In Vitro, Research Support, Non-U.S. Gov't