Antifertility activity of Carica papaya in male rats.

Abstract

AbstractA study was undertaken to verify whether the seeds of C. papaya (CP) have adverse effects on male reproduction. The bioassays for antifertility activity were carried out in rats using finely ground seeds since the rural farmers use the seeds as an anthelmintic in this form. Two trials were conducted. In trial 1, the control group had 10 animals while in trial 2, the control group had 5 animals. In trial 1, the treated rats received a dose of 0.67 g of the powder kg body weight-1 day-1 for a period of 20 days. In trial 2, the rats were treated for 44 days with a higher dose of 1.34 g/kg body weight. Five days before the end of dosing, each male was paired with a pro-oestrus female. In both trials, the weight gain was very poor compared to the controls. The weight of the testis and epididymis expressed as a percentage of the body weight did not show a significant difference between the treatment and control groups in both trials. All epididymal parameters were affected by treatment with CP. The most drastically affected parameter was the motility of cauda epididymal spermatozoa. In trial 1, two treated animals had immotile spermatozoa and in the others motility was confined to slow vibration of the tail with no forward progression. In trial 2, four treated animals had immotile spermatozoa while the other 2 had spermatozoa showing weak tail movements. A reduction in the epididymal sperm reserve and an increase in sperm abnormality were also observed. Although the highest percentage abnormality was in the head region for all groups, the tail abnormality in the treated group was 5.6 times higher than in the control in trial 1 and it was 4 times higher in trial 2. In the treated group, the mean number of implantation sites was reduced by 35.43% compared to the control in Trial 1. In this trial, of the 7 animals that were pregnant, 2 had all fetuses resorbed. As a result, the number of normal fetuses was less than the number of implantation sites. At higher dose, only 2 animals were able to impregnate receptive females. Of the 2 pregnant animals, one had only one implantation site and the other had 3. In these implantation sites, the fetuses were resorbed.