Linked Life Data

1769388

Source:http://linkedlifedata.com/resource/pubmed/id/1769388

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1992-2-21
pubmed:abstractText
The role of GABA neurones in the medial preoptic area (MPOA) in regulating the activity of the luteinising hormone-releasing hormone (LHRH) neurones projecting to the median eminence was investigated in the conscious ovariectomised rat. Plasma luteinising hormone (LH) concentrations were measured while (1) endogenous GABA release from the MPOA was monitored with the technique of microdialysis, or (2) activity at the GABA receptor was modulated by local infusions into the MPOA. Microdialysis studies revealed a fluctuating level of GABA release in the MPOA which did not correlate with pulsatile LH secretion. Infusion of 10 microM GABA (n = 8) or bicuculline methiodide (BMI, n = 6) into the MPOA, at a rate of 1 microliter/30 min, significantly inhibited mean LH concentrations (P less than 0.05-0.001) and LH pulse frequency (P less than 0.05-0.001) compared with controls (n = 8). LH pulse amplitude was not significantly altered by infusion of GABA (P greater than 0.05) while too few pulses were found after BMI treatment to enable statistical analysis. Infusions of GABA into the ventral half of the MPOA had a more significant inhibitory effect upon LH secretion compared with dorsal infusions (P = 0.012). A similar relationship did not exist for BMI infusions. These results show that acute changes in preoptic GABA receptor occupancy result in disruption of pulsatile LH secretion in the ovariectomised rat. This suggests that GABA neurones provide a tonic input important for the functional integrity of the neural network controlling LH secretion.(ABSTRACT TRUNCATED AT 250 WORDS)
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:issn
0014-4819
pubmed:author
pubmed:issnType
Print
pubmed:volume
87
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
345-52
pubmed:dateRevised
2009-11-11
pubmed:meshHeading
pubmed:year
1991
pubmed:articleTitle
Role of medial preoptic GABA neurones in regulating luteinising hormone secretion in the ovariectomised rat.
pubmed:affiliation
Department of Neuroendocrinology, AFRC Institute of Animal Physiology and Genetics Research, Babraham, Cambridge, UK.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't