Unique morphological aspects of the rat ventral prostate gland revealed byvascular corrosion casting

BACKGROUND. There is growing interest as to the potential role of the prost atic vascular system in mediating the effects of androgenic steroids on gro wth control of the prostate. Here we describe the use of a vascular corrosi on casting technique that enables the visual characterization of the vascul ar system of the rat ventral prostate and the description of some unique mo rphological features of the mature rat prostate gland that were never previ ously observed. METHODS. Anesthetized adult male Sprague-Dawley rats were vascularly perfus ed with a fixative solution and then with a catalyzed methacrylate-based ca sting solution that was allowed to polymerize in situ. Ventral prostate gla nds were dissected from these rats and the tissues were subsequently dissol ved in a corrosive solution leaving residual vascular casts. The casts were then examined by scanning electron microscopy for pertinent morphological features. RESULTS. Vascular corrosion casts of individual lobes of the mature rat ven tral, prostate revealed a complex vascular structure that entered into the prostate near the base of the bladder. The morphological correspondence of the prostatic vasculature to the previously described ductal organization o f the prostate was readily apparent. Examination of the entire vascular com plex (under low-power scanning electron microscopy) revealed three differin g surface features of the tissue and suggested that the glandular elements of the ventral prostate were directionally oriented towards a single surfac e (the anterior-lateral surface). An opposing face (posterior-medial) of th e tissue demonstrated some unique spiral vessels, suggesting the need for a potential stretch-compensation mechanism at the prostate surface immediate ly adjacent to the bladder. CONCLUSIONS. Vascular casts of the rat ventral prostate gland reveal the ob vious ductal organization of the prostatic parenchyma and demonstrate that these ducts are directionally oriented so that the glands of the prostate ( at the distal tips of the ducts) uniformly lie near the anterior-lateral su rface of the tissue. Unusual spiral arterioles found proximal to the bladde r surface suggest that the rat ventral prostate gland has acquired the mean s td adapt to an anatomical position adjacent to a tissue (bladder) that ac utely varies in size during the micturition cycle. (C) 1999 Wiley-Liss, Inc .