The relationship between sarcoplasmic reticulum Ca2+modulation proteins and postresuscitation myocardial dysfunction / 中华危重病急救医学

ABSTRACT

Objective To investigate the relationship between sarcoplasmic reticulum Ca2+modulation proteins and postresuscitation myocardial dysfunction. Methods Thirty-eight SPF male Sprague-Dawley (SD) rats were randomly divided into control group(n=12)and cardiac arrest(CA)group(n=26). CA was induced by intravenous bolus of potassium chloride(40μg/g),and cardiopulmonary resuscitation(CPR)was conducted 8 minutes later. No CA was induced in control group except catheter placement for monitoring cardiopulmonary parameters after anesthesia. Invasive hemodynamic parameters were monitored for 1 hour after CPR. Echocardiogram was performed to evaluate cardiac function. Myocardial samples were harvested 5 minutes and 1 hour after restoration of spontaneous circulation (ROSC),and sarcoplasmic reticulum Ca2+ ATPase (SERCA2a),phosphorylated phospholamban (p-PLB) and rynodine receptor(RyR)were determined by Western Blot. Results ROSC rate of CA group was 92.3%(24/26),and mean recovery time was (68 ±39)seconds. Cardiac function was significantly impaired in CA group at 1 hour after resuscitation, and ejection fraction, fraction shortening (FS), the maximal rate of left ventricular pressure increase/decline (±dp/dt max)were significantly decreased compared with those in control group 〔ejection fraction0.548±0.060 vs. 0.809±0.043,F=71.692,P=0.000;FS(34.4±4.4)%vs. (46.0±3.5)%,F=55.443,P=0.000;+dp/dt max(mmHg/s)4 718±743 vs. 7 098±394,P0.05). Conclusions The impairment of the p-PLB is closely related to postresuscitation myocardial dysfunction.