Ultrastructural changes in the Leydig cell on treatment with vincristine.

The effect of vincristine (VCR), an anticancer drug which brings about mitotic arrest by disturbing the microtubules of the spindle fibres, on the Leydig cells was investigated adopting ultrastructural and RIA of hormone techniques. The Leydig cells of VCR treated rats were necrotic and oedematous with severe damage caused to the steroidogenic machinery, viz the mitochondria and smooth endoplasmic reticulum. Such damage was duly reflected in the serum levels of hormones, wherein the androgen level was decreased with compensatory hypersecretion of follicle-stimulating hormone and luteinizing hormone. The results strongly implicate VCR in Leydig cell toxicity, and explain the problems in the reproductive performance faced by cancer patients receiving VCR as one of the drugs, both during treatment and after remission.