Steroidogenic alterations in testes and sera of rats exposed to trichioroethylene (TCE) by inhalation

Abstract

1 Trichloroethylene (TCE) is an organic unsaturated solvent used in dry cleaning, metal degreasing, thinner for paints/varnishes, anaesthetic agents etc. Human beings are considerably exposed to TCE vapours by inhalation route.

2 TCE has been reported to induce spontaneous abor- tions and congenital cardiac malformation in occupa- tionally exposed women. However, scanty on-line information is available regarding toxic effects of TCE on male reproductive efficiency in experimental animals.

3 Our earlier observations with TCE inhalation in male rats (376 p.p.m., 4 h/day, 5 days a week) for 12 and 24 weeks using whole body dynamic inhalation chamber consistently showed significant decrease (P< 0.05) in total epididymal sperm count and sperm motility. The mating experiments of above TCE inhaled rats with virgin unexposed females showed significantly de- creased fertility.

4 These observations prompted us to investigate whether or not primary testicular steroidal precursors (choles- terol and ascorbic acid) and testosterone have any role in TCE induced significantly decreased epididymal sperm count, sperm motility and overall male repro- ductive inefficiency resulting therefrom.

5 The results indicate significant decrease (P< 0.05) in total epididymal sperm count, sperm motility, specific activities of enzymes Glucose 6-p dehydrogenase (G6PDH) and 17,B hydroxy steroid dehydrogenase (1 7fHSD) with concomitant decrease in serum testos- terone concentrations in TCE inhaled rats showing reduced male reproductive efficiency. There was net accumulation in total cholesterol contents in testes of TCE exposed rats.

6 The findings in the present study indicate possible impairment of testosterone biosynthesis in TCE in- haled rats after 12 and 24 weeks. These findings also serve in parts to elucidate the mechanism of repro- ductive inefficiency in TCE exposed rats. The role of testosterone in this phenomenon is being reported for the first time.

Keywords

trichloroethylene inhalation testes testosterone;rat 17 B-hydroxy steroid dehydrogenas

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