Histological, Histochemical, and Electron-microscopic Observations on the Postnatal Development of the Major Sublingual Gland of the Rat

¹ Department of Anatomy and School of Dentistry, Dalhousie University, Halifax, Nova Scotia, Canada

The postnatal development of the major sublingual gland in rats aged from birth to 10 weeks was studied histologically and with the aid of an electron microscope. At birth, all epithelial elements within the glandular lobule were well developed. The only obvious change in the postnatal period occurred at the time of weaning (3-4 weeks), when there was a massive increase in diameter of the acini and ducts. The development of this gland was contrasted with that of the submaxillary gland in which there was a prolonged period of postnatal development and differentiation.

Additional electron-microscopic findings indicated that the secretory product of mucous acinar cells arose from Golgi vesicles, but in serous cells secretory granules appeared to arise directly in relation to endoplasmic reticulum.