Purpose: To analyze the effects of major pelvic ganglion (MPG) excision on the structure of rat prostate.
Materials and methods: We studied 80 Sprague-Dawley rats (300-350 gm. weight). Forty-two were anesthetized and the right MPG excised. After 28-30 days, the same-side prostatic ventral lobe (VL) was obtained for macroscopic, light (LM), and transmission electron microscopy (TEM) evaluation. A computerized morphometric analysis was performed on epithelial and muscle cells. Results were compared with 38 right VL of non-operated, same-aged rats.
Results: A 36.6% reduction (0.14 gm.) of VL fresh weight was found in the denervated group (p <0.001). Mean tissue proportions observed in the LM study were 27.9% (epithelial), 48.3% (stromal), and 51.8% (glandular) in the non-operated group, versus 14.8% (p <0.001), 55.7%, and 44.4% (not significant) respectively, after MPG excision. No difference was found regarding the vascular pattern. In the denervated rats, TEM analysis found a significant reduction in total and supranuclear cell height (change in cell polarity), as well as in cytoplasm, Golgi and endoplasmic reticulum areas. Secretory granule count, total area (p <0.001), and density of apical microvilli were also reduced. On the other hand, only an increase in the area of cytoplasm ribosomal aggregates was detected in the smooth muscle cell analysis.
Conclusions: Our study demonstrated a rat prostatic VL atrophy in the denervated side, due to a shrinkage in the epithelial component of the gland. Ultrastructural findings also suggest an overall decrease of epithelial cell secretory activity. Finally, the increase of ribosomal aggregates found in stromal smooth muscle could reflect an activation of these cells after denervation.