ObjectiveTo investigate the effect of salidroside on the expression of the connexin43 (Cx43) protein in the corpus cavernosum smooth muscle cells (CCSMCs) of hypoxic SD rats.

METHODSCCSMCs were cultured in vitro and identified by immunofluorescence staining. The cells were divided into six groups: normal control (21% O2), hypoxia (1% O2), hypoxia+salidroside (HS) 8 μg/ml,HS 16 μg/ml, HS 32 μg/ml, and HS 64 μg/ml, and cultured for 48 hours. Then the relative expression of Cx43 in different groups was detected by Western blot.

RESULTSThe in vitro cultured CCSMCs grew well and 90% of the cells showed positivity for α-SMA and desmin on immunohistochemistry. Salidroside ≤64 μg/ml produced no obvious toxicity on the CCSMCs. The expressions of Cx43 and phosphorylated proteins were dramatically increased in the hypoxia group as compared with the normal control (P<0.01 and P<0.05). The HS groups all showed significantly higher expression of Cx43 than the hypoxia group (P<0.01), but the phosphorylation rate of the Cx43 proteins was remarkably decreased (P<0.01).

CONCLUSIONSHypoxia increases the expression of Cx43 in the CCSMCs of SD rats. Salidroside ≤64 μg/ml cannot reverse the hypoxia-induced change but can reduce the dephosphorylation of Cx43 in CCSMCs. It is deduced that salidroside can protect CCSMCs by decreasing the phosphorylation of Cx43 and suppressing hypoxia-induced formation of the gap junction channel.