Basal cell proliferation and differentiation in regeneration of the rat ventral prostate

To determine the nature of the proliferative response of the rat ventral prostate to partial excision, parts of each lobe were excised and the residual tissue examined by light and electron microscopy. This first evidence of regrowth was the appearance of squamous cells in tubules near the wound surface with concurrent stromal proliferation but no hyperplasia of deeper tissue. A cribriform pattern of alveoli subsequently developed. Transmission electron microscopy revealed transformation of basal cells into squamous cells that contained ribosomes, polyribosomes, numerous mitochondria, tonofibrils, small to moderate amounts of rough endoplasmic reticulum, a prominent Golgi apparatus, and multivesicular bodies. These findings indicate that the regenerative response consists of basal cell hyperplasia and squamous metaplasia that is limited to the wound surface and to those tubules continuous with it.