FLOW CYTOMETRIC EVALUATION OF THE EFFECT OF VARIOUS DOSES OF VINDESINE SULFATE ON MOUSE SPERMATOGENESIS

Spermatogenesis, a rapidly proliferating cell system, is highly suscep tible to damage by radiotherapy and/or chemotherapy, Vindesine, a semi synthetic vinca alkaloid, was given as a single injection to adult mal e Swiss albino mice to study its effects on testicular weight and male germ cell turnover pattern using flow cytometry, Testicular weight de clined significantly at Day 7 to 14 and from Day 14 to 35 after admini stration of 1 and 2 mg/kg b wt vindesine, respectively. Flow cytometri c evaluation of various testicular cell types after the administration of 2 mg/kg b wt vindesine revealed a significant increase in the rela tive percentage of spermatogonial cells at Day 21 and 35 posttreatment . In contrast, the relative percentage of primary spermatocytes declin ed significantly at Day 7 and 14 posttreatment, Similarly, a significa nt reduction in the relative percentage of round spermatids was observ ed from Day 7 to 35 posttreatment. The relative percentage of elongate d spermatids declined significantly at day 35 posttreatment, These cha nges are reflected in the transformation ratios. While the 4C:2C ratio did not exhibit any significant change below 1 mg/kg vindesine, it de clined significantly after 1 mg/kg (Day 14) and 2 mg/kg (Day 7 to 35, except Day 28 posttreatment) vindesine treatment, Treatment of male mi ce with 2 mg/kg vindesine resulted in a significant decline in 1C:2C r atio from 7 to 35 d post-treatment, The 4C:S-phase ratio decreased sig nificantly at Day 7 and 14 posttreatment for all the drug doses above 0.05 mg/kg, A significant reduction in the 1C:4C ratio was observed at day 21 to 35 posttreatment as a result of 2 mg/kg vindesine administr ation. (C) 1997 Elsevier Science Inc.