Calcium Antagonists (Nifedipine and Nimodipine) and Pituitary Responses to Thyrotropin Releasing Hormone Stimulation

To assess the possible effect of the calcium antagonists nifedipine and nimodipine on the anterior pituitary responses to thyrotropin releasing hormone (TRH), seven normal males were studied in a double-blind placebo-controlled trial. The rise from basal levels of thyroid stimulating hormone (TSH) and prolactin was similar following the administration of a single therapeutic dose of either of these agents as compared to placebo. Nifedipine and nimodipine do not affect the anterior pituitary release of TSH and prolactin in response to TRH.