Safety evaluation through genotoxicity and apoptotic markers following RISUG® induced contraception and its reversal in male rabbits

The safety evaluation following vas occlusion with RISUG® and its reversal with DMSO and NaHCO3, using genotoxicity tests and apoptotic marker assays, was carried out in rabbits. Animals were divided into groups of sham operated control, vas occlusion with RISUG® for 3 & 12 months, reversal with DMSO and NaHCO3 after 3 & 12 months, respectively. Minimum incidences of micronuclei in erythrocytes and frequency of aberrant chromosomes were observed. Caspase-3 and TUNEL positive cells in testis and cauda epididymis sections were observed within control limits. Comet assay in leukocytes and testicular cells revealed damaged cell range at the control level. DNA damage in cauda epididymal spermatozoa was observed between 2-3 % by in vitro study and annexin V assay indicated a significant enhancement (p < 0.05) of positive cells in 3 months vas occlusion group. In conclusion, RISUG® induced occlusion and its reversal has not been correlated with any toxicity.