The periurethral glandular complex in the water buffalo: an ultrastructural, histological and lectin-histochemical study.

The periurethral glandular complex of the male water buffalo consists of a prostate body (not always present), a disseminate prostate and paired bulbourethral glands. The epithelium contains two types of columnar secretory cells and occasional basal cells. Type I secretory cells produce glycoprotein with a wide range of terminal sugars, these cells dominate in the cranial region of the periurethral glandular complex, whereas Type II secretory cells elaborate a mixture of carboxylated and sulphated sialomucin and prevail in the caudal portions of the periurethral glandular complex. At the ultrastructural level, Type I cells display a characteristic localization of organelles: a round nucleus in the basal portion, a Golgi apparatus and rough endoplasmic reticulum in the middle third, and secretory granules in the apical portion. Type II cells possess the ultrastructure of typical mucous cells. Following perfusion fixation of the epithelium, modifications of the lateral plasmalemmata are very obvious forming apicolateral secretory canaliculi, and intercellular channel system and a basolateral labyrinth. Nerve fibers surround the glandular basal lamina. Occasionally axons, probably of cholinergic nature, penetrate the basal lamina, then terminate in the intercellular clefts or form intraepithelial neuroglandular contacts.