Effects of a calcium antagonist on the pituitary-adrenal axis.
It has been proposed that calcium is involved, as second messenger, in the regulation of various pituitary hormones including ACTH. Several evidences indicate that calcium-entry blockers agents (i.e. nifedipine) inhibit oCRH-dependent ACTH stimulation "in vitro". To further investigate these aspects we tested the effects of a calcium antagonist nitrendipine on basal and oCRH-stimulated ACTH secretion, in 6 hypertensive patients, with normal hypothalamus pituitary adrenal axis. Nitrendipine 20 mg per os once daily for 30 days, was efficacious in lowering blood pressure but did not modify ACTH and cortisol response to oCRH (200 micrograms i.v.), in spite of a minor inhibitory effect on the concomitant aldosterone response. These data indicate that ACTH secretion is not significantly modified by calcium antagonists, which can exert a detectable effect on adrenal zona glomerulosa.
Rocco
S
S
Institute of Semeiotica Medica University of Padua, Italy.
Mantero
F
F
Boscaro
M
M
D000324:Adrenocorticotropic Hormone / Q000097:blood; D000328:Adult; D000450:Aldosterone / Q000097:blood; D001794:Blood Pressure / Q000187:drug effects; D002121:Calcium Channel Blockers / Q000009:adverse effects* / Q000627:therapeutic use; D005260:Female; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D006854:Hydrocortisone / Q000097:blood; D006973:Hypertension / Q000188:drug therapy / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D009568:Nitrendipine / Q000009:adverse effects / Q000627:therapeutic use; D010913:Pituitary-Adrenal System / Q000187:drug effects*
D002121:Calcium Channel Blockers; D000450:Aldosterone; D000324:Adrenocorticotropic Hormone; D009568:Nitrendipine; D006854:Hydrocortisone