Stereologic and fine-structural studies of prostatic acinar basal cells in the dog.

There are two distinct types of epithelial cells in the lining of the glandular acini of the prostate in adult male Beagle dogs, i.e., the columnar secretory epithelial cells and the basal cells. In contrast to the secretory epithelial cells, basal cells exhibit an abundance of micropinocytotic vesicles on their basal surface. Blood capillaries are often found in the stromal tissue in close proximity to these cells and their walls frequently display chains of fenestrations bridged by diaphragms. Stereological analysis shows that the volume density of the basal cells in the reference volume of acinar parenchyma is 0.056, and there are approximately 132.14 million cells per cm3 of prostatic tissue. An average basal cell has a volume of 373.5 micron3, and the volume densities of its nucleus, rough endoplasmic reticulum, Golgi apparatus, mitochondria and micropinocytotic vesicles, are 0.49, 0.04, 0.04, 0.094 and 0.013, respectively. These data are distinctly different from those that have been reported for the prostatic secretory epithelial cells of the same animals.