电刺激兔缺血腓肠肌预适应对再灌后心肌的保护作用

目的 研究电刺激缺血腓肠肌的预适应模式是否对缺血／再灌后的兔心肌有保护作用，并初步探讨其保护机制。方法 建立预适应的动物模型，分为对照组（Ａ组）、电刺激组（Ｂ组）、股动脉狭窄组（Ｃ组）及电刺激加股动脉狭窄组（Ｄ组）。以心率、左室功能、左室血清中一氧化氮（ＮＯ）及一氧化氮合酶（ＮＯＳ）水平为观察指标。结果 冠状动脉结扎期各组心率差异无显著性，而再灌注期间Ｃ组及Ｄ组的心率较Ａ组及Ｂ组的心率慢。与其他３组相比，再灌注４ｈ末Ｄ组的左室收缩功能指标（ＬＶＳＰ，ｄｐ／ｄｔｍａｘ）显著改善，同时左室血清中ＮＯ及ＮＯＳ水平较低（Ｐ均〈０．０５）；而Ｂ组，Ｃ组各观察指标与Ａ组相比差异无显著性。结论 电刺激缺血腓肠肌预适应模式能减轻缺血／再灌后的兔心肌损伤，其保护机制可能与ＮＯ等生物介质的效应有关。

Protective effects on ischemic myocardium produced by partial reduction of bloodsupply combined with electrical stimulation of the gastrocnemius muscle in the rabbit

Objective To determine whether partial reduction of blood supply combined with stimulation of the gastrocnemius muscle in the rabbit has protective effects on ischemic myocardium, and to study its mechanism. Methods Thirty - two rabbits were randomly divided into four groups: control group( A group), muscle stimulation group( B group),femoral artery stenosis group(C group), muscle stimulation with femoral artery stenosis group (D group). Heart rate ,changes in left ventricular functions, nitric oxide (NO) and nitric oxide synthase (NOS) in serum from left ventricle were investigated. Results During coronary occlusion, there were no differences in heart rate in all groups, but during reperfusion , heart rates in group C and group D were slower than those of group A and group B (all P<0.05); compared with other three groups, muscle stimulation with femoral stenosis preconditioning would ①improve the systolic functions of the damaged left ventricle (all P<0.05) hearly back to the baseline;②decrease NO and NOS in serum of left ventricle (all P<0.05). Conclusion The romate preconditioning model which reduce blood supply combined with rapid stimulation of the gastrocnemius muscle has protective effects on ischemic myocardium, Probably related to the changes in NO.