关键词:  哮喘；肾素-血管紧张素系统；血管紧张素Ⅱ 1型受体拮抗剂

Abstract:

Objective To investigate the relationship between the renin-angiotensin system (RAS)and asthma,and provide the theoretical basis for pathogenesis and treatment of asthma.Methods The mouse asthma models were set up and divided into control group, model group,candesartan low-dose group, and candesartan high-dose group.The serum of mice was collected, the levels of serum angiotensin Ⅱ (AngⅡ) and angiotensin Ⅰ (AngⅠ) were detected;the changes of angiotensinogen (AGT),angiotensin-convertion enzyme (ACE),angiotensin Ⅱ type 1 receptor(AT₁R) and angiotensin Ⅱ type 2 receptor (AT₂R) in the RAS of the mouse lung tissue were delected by Western blotting and RT-PCR.Results The serum Ang Ⅱ level in model group was higher than that in control group(P<0.05),but the level of AngⅡ in candesartan groups had no significant changes compared with model group（P>0.05）.The serum Ang Ⅰlevels  in each group had no significant changes（P>0.05）.The expressions of AT1R and ACE protein in model group were markedly increased compared with control group(P<0.05),the AT1R expressions in candesartan groups were significantly decreased compared with model group(P<0.05),but ACE unchanged.There were no significant differences of the expressions of AT2R protein between various groups（P>0.05）.The ACE mRNA  expression in model group was increased significantly compared with control group(P<0.05),but there was no significant change in candesartan groups compared with model group（P>0.05）.The AT₁R mRNA expression in model group was significantly increased compared with control group(P<0.05),the AT₁R  expressions in candesartan groups were significantly reduced compared with model group(P<0.05).The AT₂R mRNA in model group was significantly decreased compared with model group(P<0.05),the expressions in candesartan groups were significantly increased compared with model group(P<0.05).The expression of AGT mRNA in each group had no significant change.Conclusion In the course of asthma of mice,RAS activation is involved in the pathogenesis of asthma,and the AT₁R blocker can reverse the changes of the expressions  of ACE,AT₁R and AT₂R.

Key words: asthma；rennin-angiotensin system； angiotensin Ⅱ type 1 receptor blockers