“…Moreover, it has been suggested that hypercalcemia may have a direct vasoconstrictive action and/or mediate the release or the effect of vasoactive hormones (Pacifici, Perry, Shieber, Biglieri, Droke and Avioli 1987). A specific abnormality of the renin-angiotensin-aldosterone system or catecholamines has not been however identified in man with increased blood calcium levels due to exogenous administration (Fallo, Zangari, Luisetto, Ziliotto and Mantero 1987) or to primary hyperparathyroid function (Ganguly, Weinberger, Passmore, Caras, Khairi, Grim, Edmonson and Johnston 1982). Also, only limited information is available on the effect of changes in extracellular calcium on vascular and aldosterone responses to vasoactive agents (Bianchetti, Beretta-Piccoli, Weidmann, Boehringer, Link and Morton 1982;Brickman, Trujillo, Gutin and Tuck 1987).…”