Cadmium‐induced histomorphological changes in the testis and pituitary gonadotrophic hormone secreting cells of the cyprinid Puntius sarana

Abstract

The effect of sublethal concentrations of CdCl2 on the testis and pituitary gonadotrophic hormone (GTH) secreting cells has been studied, qualitatively and quantitatively, in Puntius sarana. Fishes exposed to 20 ppm (parts per million) concentration, for 10 days, revealed disorganization in some testicular lobules. Subsequently, there was an unusual accumulation of yellowish brown pigment in the testis. Adult males injected with 0.1 mg/ml of CdCl2 and sacrificed after 24 h exhibited histological damage similar to that of males exposed for 30 days to 20 ppm of CdCl2. In both treatments, the vascular bed of the testis was severely damaged. Interestingly, spermatids and spermatocytes appeared more sensitive than sper‐matogonia. Recovery experiments revealed that the testis had again an apparently normal aspect in fishes which, after treatment with Cd‐Cl2, were transferred into a new volume of water for 30 days. At lower concentrations, CdCl2 did not seem to influence the pituitary GTH cells. At 20 ppm concentration there was hypertrophy and extensive vacuolation of GTH cells. It was inferred that the cytotoxic damage is primarily due to the effect of CdCl2 on the vascular bed of the testis, and that the effects on the pituitary GTH cells are secondary.

Key words:

• Cadmium
• Pituitary cells
• Puntius sarana
• Cyprinids