RESUMEN
Objective To study the expression of Rho kinase and its functional activation in lung tissue from hypoxic pulmonary hypertension(HPH) rat model,and the effects of fasudil on HPH.Methods Seventy-two male Spraque-Dawley rats were randomly divided into the control group,hypoxic model group,and fasudil-intervention group[group with hypoxia and fasudil for 15 mg/(kg?d)],respectively.Mean pulmonary arterial pressure(mPAP) and right ventricle hypertrophy index(RVHI) were measured.Expression of Rho kinase mRNA and protein were examined by reverse transcriptase-polymerase chain reaction(RT-PCR) and Western blot,respectively.The phosphorylation of binding subunit of myosin phosphatase(MBS)-a substrate of Rho kinase was detected by Western blot and defined,as the mark of functional activation of the kinase.Results The expression of Rho kinase mRNA in hypoxic model group was markedly upregulated even before the onset of the third day after the experiment(HPH),and it was much lower in rats of fasudil group than that of hypoxic model group.The phosphorylation of MBS was significantly higher in hypoxic model group than that in control group,and it was positively correlated with the mPAP and RVHI(all P