Possible inhibitory influence of gamma-aminobutyric acid on growth hormone secretion in the rat.
Increasing the levels of endogenous gamma-aminobutyric acid (GABA) by treating rats with GABA-transaminase inhibitors (ethanolamine-O-sulphate and gamma acetylenic GABA) resulted in a decrease in plasma levels of GH. Diminishing GABAergic activity by inhibiting GABA synthesis with 3-mercaptopropionic acid or by blocking GABA receptors with bicuculline increased plasma concentration of GH. The presence of GABA was without effect on the basal, somatostatin-inhibited or high K+-stimulated secretion of GH by hemipituitary glands in vitro. The results suggest that GABA inhibits secretion of GH under the given experimental circumstances.
D000612:4-Aminobutyrate Transaminase / Q000037:antagonists & inhibitors; D000480:Alkynes; D000614:Aminocaproates / Q000494:pharmacology; D000818:Animals; D003864:Depression, Chemical; D004983:Ethanolamines / Q000494:pharmacology; D013006:Growth Hormone / Q000097:blood / Q000378:metabolism*; D066298:In Vitro Techniques; D008297:Male; D010902:Pituitary Gland / Q000187:drug effects / Q000378:metabolism; D051381:Rats; D005680:gamma-Aminobutyric Acid / Q000502:physiology*
D000480:Alkynes; D000614:Aminocaproates; D004983:Ethanolamines; D005680:gamma-Aminobutyric Acid; C013785:4-amino-5-hexynoic acid; D013006:Growth Hormone; C020619:ethanolamine O-sulfate; D000612:4-Aminobutyrate Transaminase