OBJECTIVETo observe the effect of Yangjing Capsule on the expressions of P-Erk1 and P-Akt1 in the corpus cavernosum of aged rats and to explore its action mechanism.

METHODSForty 24-month-old SD rats were equally randomized into an experimental and a control group, 10 selected from each group for detection of the eNOS expression before medication. The rats in the experimental group (n = 10) were treated intragastrically with Yangjing Capsule, while those in the control with physiological saline, both at 0.5 g per kg body weight per day for 4 weeks. Then all the rats were killed, and the corpus cavernosum tissues harvested for determination of the expressions of eNOS, P-Erk1 and P-Akt1 by HE staining, RT-PCR and immunohistochemistry.

RESULTSObvious distension was observed in the experimental group, but not in the control. The expression of eNOS in the rat corpus cavernosum was significantly higher after treatment than before treatment in the experimental group (24.10 +/- 2.40 vs 18.80 +/- 2.04, P < 0.05), but presented no obvious difference in the control (18.15 +/- 1.98 vs 19.35 +/- 1.50, P > 0.05), and it was remarkably higher in the former than in the latter (P < 0.05). The expression of P-Erk1 was markedly lower in the experimental than in the control rats (0.71 +/- 0.13 vs 0.83 +/- 0.17, P < 0.01), but that of P-Akt1 exhibited no remarkable difference in the same condition of GAPDH between the two groups (0.58 +/- 0.17 vs 0.48 + 0.13, P > 0.01).

CONCLUSIONBoth P-Erk1 and P-Akt were expressed in the corpus cavernosum of the aged rats. Yangjing Capsule could improve the sexual function of aged rats, which might be associated with the lowered expression of P-Erk1.