Biology of Reproduction, Vol 13, 397-407, Copyright © 1975 by Society for the Study of Reproduction

Fine Structural Localization of Cholinesterases in the Reproductive Tract of the Male White Mouse

¹ Department of Physiology Medical College of Ohio at Toledo Toledo, Ohio 43614

The distribution of cholinesterases was determined in various parts of the reproductive tract of the male mouse by Karnovsky’s method. Cholinesterases were detected in association with the endoplasmic reticulum (E. R.) and with the nuclear membrane of interlamellar cells of the seminiferous tubule of the mouse testis. Sertoli cells and maturing spermatozoa also showed strong positive reactivity in the E. R. No reaction was detected in spermatocytes and early spermatids or in the tubule lumen. In the caput epididimis, the E. R. of circular smooth muscle cells contained reaction deposits. The E. R. and nuclear envelope of the basal epithelial cells also reacted strongly. While the principal cells were devoid of the enzyme(s), the microvilli showed slight positive reactivity. Some discrete reaction particles were found in the lumen of the caput. The cauda and vas deferens contained high levels of activity in both the muscular and the epithelial layers. The reaction product surrounded the muscle bundles in the cauda and appeared in the intercellular spaces in the vas deferens, among microvilli and as free particles within the lumen. Strong activity was seen in some less dense cells towards the luminal side of the vas deferens. The spermatozoa showed no change in enzyme activity from one segment of the tract to the next as they became mature and acquired motility.