Extragonadal Effects of hCG on Calcium Homeostasis

A pilot study showed that serum calcium levels and calcium homeostasis change in response to hCG stimulation test. Serum calcium level differed when comparing pretreatment values at baseline with serum levels 72 hours after hCG stimulation in men with gonadal insufficiency referred for this stimulation test. Now we want to investigate whether this change in calcium is due to renal loss or other mechanisms and how the classical regulators of calcium homeostasis respond to hCG in men with impaired gonadal function compared with men having normal gonadal function. Moreover, the observed change in serum calcium implies that hCG also changes Phosphate, PTH and calcitonin and this will be clarified with this study