Factors Inducing Vascularization Improve the Spermatogenic and Steroidogenic Function of the Varicocelized Testis

We evaluated whether alterations in testicular vascularization and fluid dynamics have a role in the development of testicular damage in varicocelized animals. Left varicocele was induced in 6 groups of rats (A, B, C, D, E and F; 7 rats in each group). Four times a week, rats of group A, B, C, D, E and F underwent intrascrotal injections of saline, insulin-like growth factor-I, fibroblast growth factor, tumor necrosis factor-α, vascular endothelial growth factor or all the previous factors together, respectively. Additionally 7 rats were sham-operated (group G). At 8 weeks post-operation, groups E, F and G showed significantly higher left epididymal sperm content and motility, testosterone responses to human chorionic gonadotropin stimulation and intraabdominal versus intratesticular temperature differences than group A. Histological sections showed that the number of vessels per seminiferous tubule was significantly larger in groups E and F than in group A. Factors inducing vascularization have a beneficial effect on the function of the varicocelized testis attributable to improvement of testicular tissue nutrition or to amelioration of the functionality of the countercurrent heat exchange system.