A DIABETES INSIPIDUS-LIKE CONDITION PRODUCED BY SMALL DOSES OF DESOXYCORTICOSTERONE ACETATE IN DOGS

Abstract

Polydipsia and polyuria were produced in 5 normal [female] dogs by the daily inj. of desoxycorticosterone acetate (DCA) in doses of 2 and 4 mg. for 12 to 180 days. Initially, DCA caused an increase in the water intake, a gain in body wt., a reduction in urine chloride excretion and a fall in the cell vol. and Hb conc. of the blood, shortly followed by an increase in the vol. and a decrease in the sp. gr. of the urine. The intensity of the syndrome was dependent upon the dose of DCA and the amt. of NaCl in the diet (2 to 4 g.). This interdependence was demonstrated by the amelioration of the polydipsia and polyuria upon the withdrawal of salt from the diet. When symptoms were well established, water restriction decreased the polyuria but led to greater thirst and signs of tissue dehydration without hemoconcentration, while water deprivation did not elevate the urine sp. gr. to normal levels. There was a more rapid excretion of water or of a 1% saline soln. given by mouth. Pitressin was still effective in inhibiting water diuresis and diminished the excessive water exchange. The syndrome produced by DCA is essentially a disturbance in water metabolism resembling diabetes insipidus. The prolonged use of 2 to 4 mg. of DCA per day did not result in muscular weakness or other manifestations of toxicity. Upon discontinuance of the DCA injs. the water exchange promptly returned to normal.