EFFECTS OF ETHINYLESTRADIOL AND LEVONORGESTREL ON MORPHOLOGY, ULTRASTRUCTURE AND HISTOENZYMATIC ACTIVITY OF RAT-KIDNEY

Sexually mature female Wistar rats were given daily intragastric doses of ethinylestradiol (EE) and levonorgestrel (LE) used normally in wom en: (1) 0.03 mg EE and 0.05 mg LE; (2) 0.04 mg EE and 0.075 mg LE; (3) 0.03 mg EE and 0.125 mg LE. All groups were treated for 6 months in 5 -day cycles (four-day treatment with a one-day break), i.e. for 36 sex ual cycles. In rat kidneys, the activity of succinic dehydrogenase, NA DPH-tetrazolium reductase, Mg2+-ATPase and alkaline phosphatase were d ecreased, while those of lactate dehydrogenase, acid phosphatase and g lucose-6-phosphatase were enhanced. We have found a correlation betwee n enzymatic changes and ultrastructural changes in epithelial renal ce lls. These changes may reflect: (1) inhibited oxidative processes asso ciated with the mitochondrial and microsomal systems of electron trans port; (2) a compensatory increase in anaerobic processes; (3) increase d glyconeogenesis; (4) inhibited transport processes and increased cel lular catabolism. The kidney cortex and medulla did not show any signi ficant morphological changes after 6 months of treatment. The study ha s shown that EE/LE combinations produce histochemical and ultrastructu ral changes in the kidney, which are dependent on the doses of gestage ns.