Objective: To investigate the effect of Xiongcan Yishen Prescription (XYP) on the expressions of eNOS and cGMP in the penile tissue of ED rats with liver depression and kidney deficiency (LDKD).
Methods: The model of ED-LDKD was established in 30 eight-week-old SPF-class male SD rats by injecting hydrocortisone intramuscularly and binding the limbs for 14 days, and another 10 rats were taken as blank controls. Then, the model rats were randomized into six groups of equal number and treated intragastrically with distilled water (model control), tadalafil tablets at 0.52 mg/kg/d (tadalafil control), Shugan Yiyang Capsules 0.3125 g/kg/d (SYC control), and XYP at 10.4 g/kg/d (low-dose XYP), 20.8 g/kg/d (medium-dose XYP) and 41.6 g/kg/d (high-dose XYP), bid, for 28 successive days, respectively. Before and after modeling and after 28-day treatment, the animals were subjected to tail suspension and mating tests. The next day after medication, the penile tissues of the rats were harvested for determining the expression levels of eNOS and cGMP proteins by immunohistochemical analysis of the mean optical density.
Results: Compared with the model controls, the rats of the high-, medium- and low-dose XYP and SYC control groups all showed significant decreases in the tail suspension time (［3.17 ± 0.11］ vs ［2.58 ± 0.25］, ［2.52 ± 0.31］, ［2.51 ± 0.3］ and ［2.57 ± 0.29］ min, P < 0.05) and mount latency (ML) (［9.23 ± 0.11］ vs ［1.21 ± 0.12］, ［2.17 ± 0.16］, ［2.26 ± 0.13］, ［1.23 ± 0.15］ and ［2.48 ± 0.18］ min, P < 0.05) but increases in mount frequency (MF) (［0.48 ± 0.18］ vs ［3.29 ± 0.11］, ［3.18 ± 0.11］, ［3.05 ± 0.05］, ［3.23 ± 0.12］ and ［3.2 ± 0.28］ times, P < 0.05) and intromission frequency (IF) (［0.8 ± 0.84］ vs ［11.8 ± 0.84］, ［11.2 ± 1.48］, ［9.4 ± 1.14］, ［11.4 ± 1.14］ and ［10 ± 1.22］ times, P < 0.05). The eNOS and cGMP proteins were mainly expressed in the nucleus and cytoplasm of the arterial and venous endothelial cells and sinusoidal endothelial cells of the cavernous, as brownish yellow particles in a scattered and focal pattern. Both the expressions of eNOS and cGMP in the penile tissue were remarkably upregulated in the high-, medium- and low-dose XYP and SYC control groups as compared with those in the model control (P < 0.05) but exhibited no statistically significant difference between the tadalafil and model control groups (P > 0.05).
Conclusions: Xiongcan Yishen Prescription can relieve the depression symptoms, increase the mount frequency, activate the NO/cGMP pathway, and upregulate the expressions of eNOS and cGMP in the penile tissue of ED rats with liver depression and kidney deficiency.
Keywords: cyclic guanosine monophosphate; endothelial nitric oxide synthase; erectile dysfunction; liver depression and kidney deficiency; Xiongcan Yishen Prescription.