CAVERNOUS OXYGEN-TENSION AND SMOOTH-MUSCLE FIBERS - RELATION AND FUNCTION

Purpose: We studied the effect of intracavernous oxygen tension on the alteration of cavernous smooth muscle fibers in potent and impotent m en. Materials and Methods: Intracavernous oxygen tension (mm. Hg) was measured during flaccidity and 10 minutes after intracavernous prostag landin E1 injection in psychogenic control patients, and those with ve nous leakage and arterial lesions. Cavernous biopsies were performed a nd the percent of smooth muscle fibers was analyzed objectively using immunohistochemical actin anti-actin staining. Simultaneously brachial oxygen tension (mm. Hg) was measured and the cavernous brachial oxyge n tension index was then determined. Results: At flaccidity no signifi cant difference was noted in oxygen tension values among the 3 groups of patients. After prostaglandin E1 injection cavernous oxygen tension and the cavernous brachial oxygen tension index in the control group were significantly different (p < 0.01) from those of the venogenic an d arteriogenic groups (p < 0.01). The mean percent of cavernous smooth muscle fibers in the control group was significantly different from t hose of the venous leakage and arterial lesion groups (p < 0.01). Ther e was a good correlation between the percent of cavernous muscle fiber s and the value of oxygen tension before (p < 0.05) and after prostagl andin E1 injection (p < 0.01). A similar correlation was noted between cavernous muscle fibers and cavernous brachial oxygen tension index i n the different groups of patients (p < 0.01). Conclusions: Reduction of the intracavernous smooth muscle fibers in impotent patients could be explained by low intracavernous oxygen tension.