Zinc deficiency and the kidney. II. Response of zinc-deficient rats to three diuretic drugs.

Carbonic anhydrase is a zinc metalloenzyme whose activity may be affected by zinc deficiency. This investigation was designed to evaluate the effect of zinc deficiency on the response to three diuretic drugs which vary in their capacity to inhibit carbonic anhydrase: acetazolamide, furosemide and hydrochlorothiazide. The response of the zinc-deficient rats was compared to that of pair-fed and ad libitum zinc-supplemented controls. The pattern of electrolyte excretion by zinc-deficient rats in response to the three diuretics was qualitatively similar to that of the pair-fed and zinc-supplemented rats. When corrected for differences in body weight between the three groups, the natriuretic response to the diuretics in zinc-deficient rats was greater than that of either the pair-fed or zinc-supplemented controls. Although administration of the diuretics increased potassium excretion in all groups, the response of the zinc-deficient rats was attenuated. These differences in the response of zinc-deficient rats to diuretics did not appear to be related to the capacity of these drugs to inhibit carbonic anhydrase.