The effects of vasodilatation and chemical sympathectomy on spermatogenesis after unilateral testicular torsion: a flow cytometric DNA analysis

Abstract

Objective: To evaluate the effects of vasodilator therapies and chemical sympathectomy on ipsilateral and contralateral testicular spermatogenetic activity after unilateral testicular torsion using DNA flow cytometry and thus determine whether contralateral testicular damage occurs through a reflexively decreased blood flow.

Materials and methods: The study comprised four groups of 20 rats each (groups 1-4) respectively receiving isotonic saline, verapamil, pentoxifylline and 6-hydroxy dopamine hydrobromide (6-OHD) intraperitoneally. Each group was further divided into two subgroups containing 10 rats which respectively underwent either a sham operation or 720 degrees clockwise torsion applied to the left testis. The testes were harvested after 24 h and the relative proportions of haploid, diploid and tetraploid cells determined by DNA flow cytometry for each testis. The proportion of haploid cells was used as an estimate of spermatogenesis. The mean proportions of haploid cells in the groups were compared using a one-way ANOVA and paired groups were compared using Student's t-test.

Results: The proportions of haploid cells in the ipsilateral testes of rats undergoing torsion were significantly lower than in their contralateral testes and in the ipsilateral testes of the control groups. In group 4 (6-OHD) the proportion of haploid cells in the contralateral testes was significantly higher than those in the other groups after unilateral testicular torsion, but significantly lower than those in groups 1 and 4 after a sham operation. After unilateral testicular torsion the haploid cell proportions of the contralateral tests of groups 1-3 were not significantly different from each other.

Conclusions: Because the spermatogenetic activity in the contralateral testis is depressed within 24 h of ipsilateral testicular torsion, contralateral testicular damage is an acquired effect: 6-OHD offers some protection and thus the damage seems to result from the involvement of the sympathetic system.