Bull. Environ. Contain. Toxicol. (1992) 48:865--868 1992 Springer-Verlag New York Inc. i Ertvirortrnental Action of Mercuric Chloride during One Cycle of Seminiferous Epithelium in the Rat A. S. Prem, K. D. Vachhrajani, M. Bose, and K. K. Dutta Industrial Toxicology Research Centre, P. O. Box 80, Mahatma Gandhi Marg, Lucknow 226 001, India Seminiferous tubule is surrounded by peritubular membrane (PTM) which serves as primary blood-testis barrier (Dym and Fawcett,1970). Hence, its structural and functional integrity are of greater significance. Analysis of testicular toxicity of various chemicals indicated that all the seminiferous tubules did not exhibit same or similar response to a chemical (Holier, 1983; Chapin et al., 1985; Shemi et al., 1988). Hoffer (1983) described that upon administration of gossypol, less than 50~ tubules exhibit degeneration at different experimental durations. The spermatogenic cycle in rat is divided into 14 different stages of seminiferous epithelium (SE). The Sertoli cells are already shown to possess a variability of characteristics at different stages of SE (Parvinen, 1982). It has been suspected that PTM, associated with the tubules at different stages of SE, might demonstrate differential responses to a toxicant. This study investigated the action of mercuric chloride (MC) on the peritubular membrane at different stages of SE in rats. MATERIALS AND METHODS 30 male albino rats (Wistar, 250-+I0g), maintained in standard laboratory conditions were divided into two groups. Single i.p. dose of HgCI~ (lmg/kg; 5~ of LD~n value) was given to the animals of group ~II (n=18). Control ~ts group I (n--12) were given distilled water. Animals were sacrificed on 1,3,5,8 and 12 days post exposure. This duration was selected because one cycle of SE in rat takes around 12 days. On each of the experimental duration , 2 rats from control group and 3 rats from treated group were sacrificed by cervical dislocation. Testes were cleanly dissected out and fixed in Bouin~s fluid, 5 ~m paraffin sections were stained with hemat- oxylln and eosin. The stages of SE and various spermatogenic cell types were identified. The status of seminiferous perltub- ular membrane (PTM), intactness of germinal epithelium and Address correspondence to Dr.K.K.Dutta on above address. 865