[The hypothalamo-hypophyseal system: the role of calcium ions]

The Authors investigated the effects of Verapamil a calcium antagonist substance upon the pituitary response to several secretogogus agents in ten male healthy subjects in order to elucidate the calcium role in the regulation of the hypothalamic pituitary function. As a consequence of Verapamil administration (5 mg iv) a significant hyporesponsiveness of FSH and LH to GnRH (100 micrograms iv) of TSH to TRH (200 gamma iv) and of ACTH to insulin induced hypoglycemia was observed. Prolactin response to TRH (200 gamma iv) was not modified by Verapamil treatment. The Authors concluded emphasizing the importance of Ca++ in the modulation of diencephalic pituitary activity.