Inhibition of renal electrolyte excretion by gabaergic pathways of the lateral hypothalamic area

Injection of gamma amino butyric acid (GABA) into the lateral hypothalamic area of unrestrained conscious rats caused a decrease in renal electrolyte excretion with an increase in urinary flow. When picrotoxin, a specific inhibitor of gabaergic pathways, was administered, a significant increase in renal water and electrolyte excretion occurred. The effect of simultaneous injection of picrotoxin and GABA into the same site indicated that picrotoxin was less potent in reversing the effect induced by GABA than GABA was in reversing the effect of picrotoxin. We conclude that GABA acts directly on the neuronal mechanisms involved in the control of water and electrolyte excretion, perhaps by exerting a tonic inhibitory action on renal electrolyte excretion.