THE RELEASE OF HISTAMINE FROM TISSUE SLICES OF RAT HYPOTHALAMUS1

Abstract
Abstract— The efflux of endogenous histamine from small slices of rat hypothalamus has been studied. Histamine release was temperature dependent and could be increased 50 % after depolarization of the brain slices by 15 mm potassium. The presence of EDTA in the incubating media inhibited the release of histamine and blocked the effect of potassium. Theophylline and reserpine markedly increased release of histamine, whereas phenoxybenzamine inhibited release and blocked the effects of theophylline and reserpine. Efflux of histidine from hypothalamic tissue slices was not temperature‐dependent and was unaffected by the addition of potassium or any of the drugs studied.