Pituitary-adrenocortical response to metoclopramide in patients with acromegaly and prolactinoma: A clinical evaluation of catecholamine-mediated adrenocorticotropin secretion

Seikoh Nishida, Michihiro Matsuki, Noriko Adachi, Masaharu Horino, Masaya Yoneda, Masahiko Endoh, Hideki Oyama, Masahisa Kikuoka, Ryoichi Otsuka, Ryoji Ishii, Chiyo Andoh

Research output: Contribution to journalArticle

9 Citations (Scopus)

Abstract

We have demonstrated that metoclopramide stimulates cortisol secretion at least in part by a stress-mediated effect in normal men. To examine further the effect of the drug on the hypothalamo-pituitary adrenal system, we studied the cortisol response to 20 mg metoclopramide in patients with acromegaly, prolactinomas, and functional hyperprolactinemia and compared the results with the responses to insulin-induced hypoglycemia. In some patients, the effects of metoclopramide on CRH-induced ACTH and cortisol increase were studied to determine whether a change in dopaminergic (catecholaminergic) activity altered CRH stimulation of pituitary-adrenal function. No cortisol response to 20 mg metoclopramide occurred in 13 tests on 8 of 9 patients with prolactinoma or acromegaly with hyperprolactinemia, whereas both acromegalic patients without hyperprolactinemia had a response. All of the patients had a normal cortisol response to insulin-induced hypoglycemia. Pretreatment with metoclopramide enhanced the CRH-induced cortisol increase from 30–120 min after CRH in normal men, but only at 15 and 30 min in 5 agromegalic patients. The results suggest that metoclopramide acts in the hypothalamus to release ACTH through a dopamine antagonist-mediated (catecholaminergic) mechanism, and that metoclopramide may act additively with CRH to stimulate ACTH secretion in normal men. The absence of a metoclopramide-induced cortisol response in patients with acromegaly or prolactinomas and the absence of a normal cortisol response to metoclopramide-CRH in acromegalic patients could be due to endogenous catecholamine deficiency in these patients.

Original languageEnglish
Pages (from-to)995-1001
Number of pages7
JournalJournal of Clinical Endocrinology and Metabolism
Volume64
Issue number5
DOIs
Publication statusPublished - 1987 May

    Fingerprint

ASJC Scopus subject areas

  • Endocrinology, Diabetes and Metabolism
  • Biochemistry
  • Endocrinology
  • Clinical Biochemistry
  • Biochemistry, medical

Cite this