AB040. The effects of nicotine- and tar-free cigarette smoke extract on plasma testosterone level and erectile function in rats

OBJECTIVE: To evaluate the effects of nicotine- and tar-free cigarette smoke extract on plasma testosterone level and erectile function in rats. METHODS: Thirty male Sprague-Dawley (SD) rats were randomly divided into 3 groups (n=10): the control group (PBS group), fCSE group and antioxidant group (CSE + GSH group). After 8 weeks, by electrostimulating of the cavernous nerve, maximal intracavernous pressure (MICP), mean arterial pressure (MAP), ICP/MAP, Tmax (the time of stimulating MICP happened), cavernosal filling rate (CFR) were measured with radioimmunoassay to evaluate the erectile function of rats;the levels of plasma testosterone(T) were measured with radioimmunoassay, the activity of superoxide dismutase (SOD), MDA, NOS, from cavernosal tissue homogenate was measured .To observe the morphological changes of corpus cavernosum tissue by Masson staining RESULTS: Compared to the control group [T (5.37±1.43) μg/L, NOS (2.90±0.27) U/mg, SOD (18.41±1.09) U/mg prot], fCSE group [T (3.22±1.11) μg/L, NOS (1.67±0.18) U/mg, SOD (13.36±1.18) U/mg prot] decreased obviously. About index of erectile function, compared to the control group [MICP (85.92±6.36) mmHg, MICP/MAP (0.86±0.09) and CFR (2.14±0.44)], fCSE group [MICP (58.99±10.76) mmHg, MICP/MAP (0.56±0.08), CFR (0.89±0.44)] decreased obviously; and Tmax [(29.90±5.78) vs. (42.90±8.56) s] delayed obviously, and the levels of T were positively correlated with CFR (r=0.364, P<0.05). Compared with the control group, Masson staining showed that fCSE group of the fiber about corpus cavernosum smooth muscle tissue/collagen fiber decreased obviously [(+0.27 0.04) vs. (0.98+0.12)]. Antioxidant group could improve index of erectile function, but there was no obvious effect in improving the ratio of the corpus cavernosum smooth muscle tissue/collagen fiber CONCLUSIONS: The decrease of nicotine- and tar-free cigarette smoke extract on plasma testosterone level and erectile function in rats was related to oxidative stress, Antioxidant therapy could improve erectile function, but it was limited in protecting penis organization.