Morphology of the prostate gland in the nine-banded armadillo

Abstract

The prostate of the nine-banded armadillo is a compound tubulo-alveolar, bilobed gland situated on the ventral surface of the seminal vesicles. The two lobes, which may be connected by a narrow isthmus of tissue, are encapsulated by a thin layer of connective tissue and are located peripheral to the urethral musculature. The acini within the gland are separated by a fibromuscular stroma and contain an amorphous secretory product. The mucosa, characterized by a simple columnar epithelium, is thrown into folds which frequently branch. Numerous secretory ducts arise from the gland and course caudally parallel to the vasa deferentia and ducts of the seminal vesicles to a tubercle on the wall of the urethra. Several secretory ducts open into the vasa deferentia near the latter’s termination at the urethra, while other prostatic ducts empty directly into the urethra. The columnar cells of the mucosa resemble protein secretory cells with a spherical nucleus in the basal portion of the cell and numerous secretory granules located in the apical region of the cell. The rough endoplasmic reticulum is a complex network of stacks of interconnecting cisternae and tubules which is often connected to the nuclear envelope. The Golgi apparatus is extensive and is located in the supranuclear region of the cell. The secretory ^granules appear in various sizes and densities and seem to be released by exocytosis.