Light and electron microscopic study of the postnatal prostate in male Praomys (Mastomys) Natalensis.

The postnatal development of the prostate was studied in male Praomys (Mastomys) Natalensis using both light and electron microscopy. At birth, the ventral and dorsal lobes consist of cords of cells that previously budded from the urogenital epithelium into condensed pads of stroma. The ventral cords have developed small lumina, whereas lumina do not develop in the dorsal lobe until two days after birth. The cords and tubules lengthen, branch, and coil so that by six days, the tubules of the ventral lobe almost completely make up the substance of the enlarged prostate, and those containing the larger lumina have only one to two cell layers surrounding them and contain a small amount of secretory product. The dorsal lobe, however, remains composed of small tubules. The ventral prostatic acini of the 12 day animal develop epithelial infoldings, the lining cells increase in height, and many acquire supranuclear light areas. The dorsal lobe acini remain smaller than those of the ventral lobe and are lined by cuboidal cells. Their secretion is evident at 18 days. By one month, the ventral and dorsal prostates of the male Praomys appear similar to those of the adult. Thereafter, changes include increase in size, acinus number and size, and epithelial involutions as well as the development of more prominent supranuclear light areas in the ventral prostatic epithelial cells.