Effect of isoproturon on male reproductive system: clinical, histological and histoenzyonological studies in rats.

ABSTRACT

Isoproturon, a nonhalogenated substituted phenylurea herbicide, was evaluated for its cumulative toxic effects on testicular histomorphology., steroid hormone biosynthesis-related enzymes, spermatogenesis and sperm cells in adult albino rats. The compound, suspended in refined groundnut oil, was administered (po) to rats for 10 weeks @ 0,200, 400 and 800 mg/kg/day for 6 days/week. Isoproturon, at 800 mg/kg dose, decreased epididymal sperm count and percentage of motile sperms and increased the percentage of morphologically abnormal sperm cells. At the same dose, diameter of seminiferous tubules was reduced, number of tubules per microscopic field was increased and the percentage of tubules with evidence of spermatogenesis decreased. However, the percentage of damaged tubules was increased with 400 and 800 mg/kg doses. Histoenzymological observations revealed dose-related reduction in the activities of glucose-6-phosphate dehydrogenase and delta 5-3 beta-hydroxy steroid dehydrogenase. Activity of 17 beta-hydroxy steroid dehydrogenase was not affected appreciably. Overall findings suggest that isoproturon, at high dose, impairs androgen biosynthetic process, affects spermatogenesis and induces maturational anomalies of sperm cells in rat.