Effects of Carica papaya (paw paw) seeds extract on the morphology of pituitary-gonadal axis of male Wistar rats.

The effects of oral administration of Carica papaya seeds extract on the morphology of pituitary, testes and sex accessory glands were studied. The C. papaya extract (50 and 200 mg/kg/day) was administered orally to sexually mature male Wistar rats for 1 and 8 weeks, respectively. The control group received corn oil (vehicle) only. The animals were killed after 1 and 8 weeks treatment for histological preparation. The microscopic examination of the sections of pituitary gonadotrophs (FSH and LH cells) treated with 200 mg/kg of C. papaya extract showed pronounced hypertrophy, while section of rats treated with 50 mg/kg showed mild hypertrophy and hyperplasia. Whereas the testes of rats treated with C. papaya extract at 50 and 200 mg/kg revealed gradual degeneration of germ cells, Sertoli cells and Leydig cells as well as germinal epithelium. However, tubules of epididymes of rats treated with extract, 200 mg/kg, appeared empty indicating the degeneration of sperm cells in the lumina. The sections of prostate glands of rats treated with 200 mg/kg extract showed coagulation of secretion in the lumina as well as empty tubules with cell debris, while the effect was reduced in rats treated with 50 mg/kg. The seminal vesicles showed progressive collapse and shrinkage of villi. These results suggest that C. papaya extract interfered with the pituitary - gonadal axis to influence male reproductive functions, which confirmed its antifertility property as reported previously. Copyright 2005 John Wiley & Sons, Ltd.