Do experimentally induced ipsilateral testicular torsion, vas deferens obstruction, intra-abdominal testis or venous obstruction damage the contralateral testis through a common mechanism?

Objective To evaluate if various conditions affecting the ipsilateral testi s which also damage the contralateral testis share a common pathway for the ir effects. Materials and methods The study comprised five groups of 10 adult rats whic h underwent surgery to produce (on their left sides); group 1, a sham opera tion (control); group 2, testicular torsion; group 3, vas deferens obstruct ion; group 4, an intra-abdominal testis; and group 5, venous obstruction. T he ipsilateral and contralateral testes were harvested 4 weeks after surger y. The relative proportions of haploid cells, the mean seminiferous tubular diameter (MSTD), mean testicular biopsy scores (MTBS), and lactate and hyp oxanthine levels were determined and compared, Results The proportions of haploid cells in the ipsilateral and the contral ateral testes of groups 2-5 were significantly lower than those of the corr esponding testes of the control group. The MSTD and MTBS of the ipsilateral testes in groups 2-5 were also significantly lower than the ipsilateral te stes of controls and the contralateral testes within the same groups. While the MSTD and MTBS of the contralateral testes of groups 1 and 5 were not s ignificantly different, those of the contralateral testes of groups 2-4 wer e significantly less than that of group 1, The lactic acid and hypoxanthine levels of the ipsilateral and contralateral testes were significantly incr eased in groups 2 and 3. While only the hypoxanthine level of group 5 incre ased significantly, both variables were not significantly different between the ipsilateral testes of groups 1 and 4, Conclusions These four treatments damaged both the ipsilateral and contrala teral testes. As the lactic acid and hypoxanthine levels within the contral ateral testis were greater than in the controls, testicular torsion and vas deferens obstruction seem to share a common pathway (which may be a reflex decrease in contralateral testicular blood flow) for their effects on the contralateral testis.