Morphological alterations in the seminiferous tubules of adult Wistar rats: the effects of prenatal ethanol exposure

Abstract

This study presents the effects of prenatal ethanol exposure on the morphology of the seminiferous tubules of the testes in the adult male rat. Timed-pregnant adult female Wistar rats (average weight 200 g) were given daily intragastric intubation of 5.8 g/kg ethanol between gestation days 9 and 12. Pair-fed and ad lib-fed animals served as controls. The pups were weighed at birth and weaned at 30 days. At 42 days of age the male offspring (n = 10) from each group were anaesthetised and the testes removed and weighed. Another set of male rats from each group (n = 6), were anaesthetised, whole body perfused and the testes removed and processed for paraffin embedding. Sections were subjected to morphological analysis and morphometric measurements based on computerised techniques following haematoxylin and eosin, PAS and reticulin staining. The results demonstrated that prenatal ethanol exposure induced persistent growth retardation and a 66% reduction in testicular weight and severely altered the morphology of the seminiferous tubules of adult male rats, causing a reduction in the cross-sectional area of the tubules by 18%, germinal epithelium thickness by 21% (p < 0.001) and an inhibition of spermatogenesis. The study showed the absence of reticulin fibres in the peritubular tissue of seminiferous tubules of prenatal ethanol-exposed adult male rats. The results imply that damage following prenatal ethanol exposure occurs irreversibly in utero and persists into adulthood in the exposed animals, which may have implications for male fertility.