Morphometric analysis of rat testis following chronic exposure to cigarette smoke

To assess the effect of chronic exposure to cigarette smoke on spermatogenesis in Sprague-Dawley rats.

Twenty 5-day-old Sprague-Dawley rats were exposed daily to cigarette smoke by the Walton smoking machine for a period of 15, 30, and 45 days. Age-matched Sprague-Dawley rats exposed to room air with the smoking machine served as controls. Rats were sacrificed from each group at 15, 30, and 45 days and the testes were removed. Fifty seminiferous tubules were assessed in each group. Morphometric and histopathologic analyses of the testes were carried out. The following parameters were studied: (1) Number of germ cells (step 7 spermatids), (2) seminiferous tubule diameter, (3) height of germinal epithelium, (4) presence of degenerating or sloughed cells, (5) failure of release of spermatids into the tubular lumen, and (6) degeneration of Leydig cells. Statistical analysis was performed using ANOVA followed by the t test.

There was a significant decrease in the germ cell count (step 7 spermatids) in the rats exposed to cigarette smoke for 30 days (93.19 versus 98.15 step 7 spermatids in the control animals (p < 0.001). This decrease persisted in the rats exposed to cigarette smoke for 45 days (82.47 versus 103.01 step 7 spermatids in control animals, p < 0.001). The mean seminiferous tubule diameter was significantly reduced only in the rats exposed to cigarette smoke for 45 days (0.283 microm versus 0.299 microm in the control animals, p < 0.001). There was no significant difference in the height of the germinal epithelium, and no degenerating cells were noted in either group.

Cigarette smoke adversely affects spermatogenesis in pubertal Sprague-Dawley rats.