gamma-Aminobutyric acid antagonist blocks baroreceptor-activated inhibition of neurosecretory cells in the hypothalamic paraventricular nucleus of rats.
The effects of gamma-aminobutyric acid (GABA) antagonists on baroreceptor-activated inhibition of neurosecretory cells in the paraventricular nucleus (PVN) were examined in urethane-chloralose anesthetized rats. In 11 neurosecretory cells which were inhibited by baroreceptor activation induced by intravenous application of phenylephrine, microiontophoretically applied bicuculline and/or picrotoxin blocked the inhibition (n = 9) completely or partially, whereas strychnine (n = 4) did not. The results suggest that GABA is, at least in part, involved in the baroreceptor-activated inhibition of PVN neurosecretory cells.
Department of Physiology, University of Occupational and Environmental Health, School of Medicine, Kitakyushu, Japan.
M
M
Kasai
T
T
Osaka
K
K
Inenaga
H
H
Kannan
H
H
Yamashita
D000200:Action Potentials / Q000187:drug effects; D000818:Animals; D001640:Bicuculline / Q000494:pharmacology*; D018756:GABA Antagonists; D008297:Male; D009490:Neurosecretory Systems / Q000187:drug effects*; D010286:Paraventricular Hypothalamic Nucleus / Q000187:drug effects / Q000378:metabolism*; D010656:Phenylephrine / Q000494:pharmacology; D010852:Picrotoxin / Q000494:pharmacology*; D011311:Pressoreceptors / Q000187:drug effects / Q000502:physiology*; D051381:Rats; D011919:Rats, Inbred Strains; D013331:Strychnine / Q000494:pharmacology; D005680:gamma-Aminobutyric Acid / Q000502:physiology
D001640:Bicuculline; D018756:GABA Antagonists; D010656:Phenylephrine; D010852:Picrotoxin; D013331:Strychnine; D005680:gamma-Aminobutyric Acid