Metoclopramide does not elevate aldosterone in the rat

Abstract

The aldosterone response to metoclopramide (MCP), reported in man and sheep, suggests the existence of a novel aldosterone-regulating mechanism. However, the mechanism and site of action of MCP, whether adrenal or extraadrenal, in the stimulation of aldosterone production in vivo remain to be defined. We have investigated the effect of MCP in the rat in vivo on urinary aldosterone excretion, plasma aldosterone, and aldosterone MCR; in addition, we have examined its in vitro effects on steroidogenesis by isolated zona glomerulosa cells. MCP (0.01-100 mg/kg), given by ip injection to conscious rats, was without effect on urinary aldosterone excretion, despite an 8- to 10-fold response to potas..