Effects of Acute Administration of Porcine and Salmon Calcitonin on Urine Electrolyte Excretion in Rats

Acute sc administration of natural salmon CT to fasted male rats, at a dosage of 0.5 MRC U/100 g or greater, produced an alkaline diuresis, natriuresis, hypercalciuria, hyperphosphaturia, and hypomagnesuria. Urine potassium and creatinine were less markedly, but significantly, elevated. During the 5-hr observation period, hypocalcemia and hypophosphatemia were apparent, with no consistent changes in blood sodium, potassium, magnesium, or pH. Similar results were obtained in rats given an intraperitoneal saline load. In the same assay system, porcine CT, at doses up to 2.0 U/kg sc, produced similar blood changes, but did not influence urine parameters.