The effect of nifedipine on serum parathyroid hormone and calcitonin in postmenopausal women.

The effect of calcium channel blockers on calcium homeostasis in postmenopausal osteoporotic women with arterial hypertension has not to date been defined. In the submitted study, the influence of nifedipine on serum parathyroid hormone (PTH), calcitonin and osteocalcin is followed in 11 patients. After one month of treatment, serum PTH markedly declined in all women and osteocalcin decreased in 10 patients. In contrast, serum calcitonin increased in five patients, whilst in another five the effect was just the opposite. In one woman this indicator was not affected. There are no mutual correlations between the mentioned indices. In conclusion, the calcitonin secretory process is not sensitive to calcium channel blockade within the present study. In spite of the fact that nifedipine inhibits PTH secretion in postmenopausal osteoporotic women, the direct effect of the drug on osteoblasts (not mediated by PTH) cannot be excluded.