The Sertoli cell membrane body in the skink.

The structure of the Sertoli cell and its physical relationship with the germ cells was studied in laboratory maintained skinks, Eumeces laticeps (Schneider) in January, and September, corresponding to the periods of prenuptial and postnuptial spermatogenesis respectively. Light micrographs obtained using 1 micron thick plastic sections, show the Sertoli cell to have a large polymorphic nucleus located in the basal portion of the cell, and a darkly staining juxtanuclear body. In ultrathin sections, this body consists of a complex array of thin, electron dense membranous structures resembling the endoplasmic reticulum. The lumina of these membranous channels appear empty. Between the channels, there are structures that resemble the expanded cisternae of the endoplasmic reticulum. In some sections, these dilated cisternae are confluent with the channels, indicating that the channels and the cisternae are parts of the same structure. Three organelles, namely, mitochondria, lysosomes and microfilaments are found among the elements of the membrane body. There is no structural modification of the channels where they come in contact with mitochondria, but they are dilated in proximity to lysosomes. In some sections bundles of microfilaments are clearly visible within the diamond shaped region of contact between two channels, suggesting that these organelles are involved in structural or functional organization of the membrane body.