Effect of Thyrotropin-Releasing Hormone on Gastric Acid Secretion in Man

Abstract

Thyrotropin-releasing hormone (TRH) has been shown to have a dose-dependent inhibiting effect on the pentagastrin-stimulated gastric acid secretion in man. We studied the effect of increasing doses of TRH on the gastric acid secretion stimulated by a submaximal histamine dose. The effect of a relatively high dose of TRH (500 μg/h) on the maximal histamine-stimulated acid secretion was examined. Furthermore, we studied the effect of two doses of TRH (40 μg/h and 500 μg/h) on the gastric acid output after insulin-induced hypoglycemia. A significant reduction of the submaximal histamine-stimulated gastric acid output was observed during infusion of 8 μg/h TRH (16%), 40 μg/h TRH (38%), and 200 μ/h TRH (42%) (percentage reduction compared with the control experiment). TRH, 1000 μg/h, had no significant effect. With regard to the acid output after maximal histamine stimulation, TRH 500 μg/h was without significant effect. After hypoglycemia the acid output was reduced by 30% during 40 μg/h TRH (p < 0.05) and by 37% during 500 μg/h TRH (p < 0.02). TRH had no effect on the acid concentration in any of the studies. The possible mechanisms by which TRH may interact with the acid regulation are discussed.