The Influence of Calcium Infusion on Serum Prolactin in Hyperprolactinemic Women

: This study investigated the influence of calcium on serum prolactin (PRL) in hyperprolactinemic and healthy women. Previous studies have shown an inhibitory effect of Ca2+ on serum PRL, related to the degree of hypercalcemia. Serum PRL levels were measured by immunoradiometric assay (IRMA) in subjects before and one hour after 1375 mg Ca2+ injection. Serum PRL level was significantly decreased by calcium injection in hyperprolactinemic women (89.2 +/- 29.1 and 63.3 +/- 35.8 ng/ml; p 0.05) in women with normal PRL levels (12.6 +/- 5.1 ng/ml and 11.3 +/- 4.0 ng/ml). These results indicate that acute alterations in serum calcium levels affect PRL secretion in hyperprolactinemic women.