CHANGES IN ZINC STATUS AND SOME SIDE-EFFECTS ON LONG-TERM DIURETIC THERAPY IN GROWING RATS

Ninety-nine male Sprague-Dawley rats with an initial average life mass (LM) of 46 g were divided into 11 treatment groups of 9 animals each. For 28 days they received ad libitum semisynthetic purified diet on the basic of casein without zinc (treatment 1) or supplemented with 4 mg Zn/kg DM (treatment 2), respectively 56 mg Zn/kg DM (treatment 11). All other treatment groups received a diet supplemented with 4 mg Zn/kg DM and an addition of the diuretics acetazolamide, furosemide, hydrochlorothiazide or triamterene in therapeutical doses (treatments 3, 5, 7 and 9) or in doses corresponding to their chronical toxicity (treatments 4, 6, 8 and 10). In comparison with treatment 2 (8 mg Zn/kg DM), neither the therapeutical dose nor the dose corresponding to their chronical toxicity of acetazolamide, furosemide, hydrochlorothiazide and triamterene applied in treatments 3 - 10 (8 mg Zn/kg DM) did markedly alter the average life mass at the end of the experimental period. Hydrochlorothiazide and triamterene, given as a therapeutical dose (treatments 7 and 9) or a dose corresponding to their chronical toxicity (treatments 8 and 10), increased the zinc status significantly, when compared to the corresponding control (treatment 2). The elevation in zinc status after alimentary application of hydrochlorothiazide and triamterene in treatments 7 - 10 was documented by a higher zinc concentration in serum than that of treatment 2. In comparison with treatment 2, also the tendency towards an increase in the serum zinc concentration as well as the significantly elevated activity of the alkaline phosphatase in serum of treatment 6 supplemented with 8 mg furosemide/kg LM(0.75)/d indicated an elevated zinc status of this treatment group. On the other hand 5, respectively 41 mg acetazolamide/kg LM(0.75)/d and 3 mg furosemide/kg LM(0.75)/d applied in treatments 3, 4 and 5 had no significant effect on the serum zinc concentration and activity of the alkaline phosphatase in serum, which behaved in the same way as in the control group.