The Effect of Cold Baths after Hot Baths on Spermatogenesis in Rat Testicles

Lee, Jae Gue; Park, Kwang sung

Abstract

PURPOSE: It has been reported that exposure of the testicles to high temperature through frequent saunas or hot baths causes impairment of spermatogenesis, however, there are few studies which offer ways to prevent it. The aim of this study is to evaluate the effect of a cold bath in preventing impaired spermatogenesis caused by exposure to a hot bath in the rat model.
MATERIALS AND METHODS
Forty-five white male Sprague-Dawley rats (200-230gm) were divided into 3 groups; control, hot bath, hot followed by cold bath groups. The hot bath group was assigned to the hot bath (41-43oC) for 10 minutes and then exposed to the room temperature (23-24oC) for 3 minutes, whereas the hot followed by cold bath group was assigned to the cold bath (18-20oC) after the hot bath. Each procedure was repeated twice daily and 3 days a week for 4 weeks. Five randomly selected rats from each group were sacrified just after baths, and 4 and 8 weeks later. The testicular weight, the mean numbers of mature spermatids, Sertoli cells, spermatid to Sertoli cell ratio and tubular diameter were measured in each group. Two way analyses of variance (ANOVA) were performed for a statistical analysis.
RESULTS
Just after completion of baths, the weight of testicle, the number of mature spermatid cells, the spermatid to Sertoli cell ratio and the tubular diameter significantly decreased in the hot bath group (0.71 +/- 0.08g, 0 +/- 0, 0 +/- 0, 0.20 +/- 0.01mm) compared to the control group (1.57 +/- 0.67g, 139.85 +/- 29.70, 7.24 +/- 1.36, 0.32 +/- 0.02mm), re spectively (p<0.05). However, there was no significant difference between the hot followed by cold bath group (1.36 +/- 0.20g, 127.00 +/- 26.14, 6.30 +/- 1.14, 0.31 +/- 0.01mm) and the control group, respectively. On the other hand, there was no significant dif ference between the hot bath group and the control group in the number of Sertoli cells per seminiferous tubules (p=0.110). After 4 and 8 weeks, the number of mature spermatids improved in the hot bath group despite showing significantly decreased findings compared with the control and hot followed by cold bath groups.
CONCLUSIONS
The hot bath treatment significantly decreased spermatogenesis in the testicles of the male rat, whereas it was preserved in the cold bath after the hot bath. This result suggests that a cold bath is recommanded immediately after a hot bath to help impaired spermatogenesis caused by frequent hot baths.