重组人生长激素对心肌梗死大鼠心功能及心肌炎性因子表达的影响

目的 观察重组人生长激素(rhGH)对大鼠急性心肌梗死后心功能及心肌炎性因子表达的影响. 方法 结扎大鼠左冠状动脉前降支建立心肌梗死模型,将术后24 h存活的大鼠随机分为对照组和rhGH组,另设假手术组.rhGH组给予rhGH 2 mg.kg-1.d-1皮下注射,对照组和假手术组给予等体积的生理盐水皮下注射,4周后观察rhGH对大鼠心功能及心肌细胞肿瘤坏死因子-α(TNF-α)、白介素-1p(IL-1p)、白介素-6(IL-6)、白介素-10(IL-10)mRNA表达的影响. 结果 与假手术组比较,对照组心肌组织中促炎性细胞因子TNF-α、IL-1β、IL-β和IL-10 mRNA表达(假手术组分别为0.10±0.02、0.08±0.01、0.18±0.01和0.14±0.05;梗死区分别为0.77±0.15、0.93±0.17、1.10±0.14和0.73±0.11;非梗死区分别为0.88±0.14、0.95±0.17、1.18±0.11和0.83±0.16)明显升高.与对照组比较,rhGH组心肌组织中TNF-α、IL-1β、IL-6 mRNA表达(梗死区分别为0.35±0.10、0.36±0.10、0.43±0.11;非梗死区分别为0.51±0.10、0.42±0.11、0.51±0.12)明显下降,IL-10 mRNA表达(梗死区为1.18±0.18;非梗死区为1.21±0.22)升高,P＜0.05.心脏超声显示rhGH组左室功能明显改善. 结论 早期rhGH治疗改善了心肌梗死大鼠心肌炎性因子表达和心脏功能.rhGH有效改善心功能与其降低心肌细胞促炎细胞因子和升高抗炎因子的作用有关.

Effects of recombinant human growth hormone on myocardial inflammatory eytokine expression and heart function in rats with acute myocardial infarction

Objective To explore the effects of recombinant human growth hormone(rhGH)on myocardial inflammatory cytokine expression and heart function in rats with acute myocardial infarction (AMI). Methods Rats with AMI induced by left anterior descending coronary branch ligation were randomized to rhGH and control groups compared with sham-operated group. The effects of 4 weeks of therapy with GH starting 24 hours after myocardial infarction on myocardial cytokines expression and heart function were studied. Myocardial inflammation was examined by analyzing the myocardial cytokine production including the pro-inflammatory cytokines: interleukin (IL)-1β, IL-6 and tumor necrosis factor (TNF)-α and the anti-inflammatory cytokine: IL-10. Echocardiography was used to evaluate heart function. Results The levels of TNF-α, IL-1β, IL-6 and IL-10 in the infarcted and non-infarcted region of control group were markedly elevated compared to sham-operated group (all P＜0.05). After 4 weeks therapy, rhGH reduced the expression of TNF -α, IL-1β, IL-6 and increased IL-10 expression in the infarcted and non-infarcted region of rhGH group compared to control group (all P＜0. 05 ). Echocardiography showed that rhGH markedly improved left heart function (P＜0. 05 ). Conclusions Early rhGH treatment can improve heart function and myocardial inflammatory cytokine expression after AMI. One of immunopharmacologic mechanisms underlying the beneficial effects of rhGH on heart function improvement may involve the attenuation of pro-inflammatory cytokines and the increase of anti-inflammatory cytokine levels in cardiac myocytes.