ABSTRACT
Objective To investigate the effects of PPAR-gamma expression on reperfusion arrhythmias in different precon ditioning myocardial ischemia/reperfusion(I/R) animal model.Methods Thirty-two SD rats were randomly divided into 4 groups(n =8):rosiglitazone+ I/R group (ROS group),GW9662 + I/R group(GW group),I/R group and sham group (Sham group).The I/ R animal model was constructed by ligation of the left anterior descending coronary artery,with ischemia for 30 min and reperfusion for 120 min.The dynamic limb Ⅱ lead electrocardiogram monitoring was performed;PPAR-gamma mRNA was detected by fluorescent quantitative PCR and the change of PPAR-gamma protein expression was detected by Western blot.Results The increasing range of QRS wave width detected before operation,at 30 min of ischemia,at 1,2 h of reperfusion from large to small were in turn the ROS group,I/R group,GW group and Sham group;the reperfusion arrhythmia score in the ROS group was significantly higher than that in the other groups(P＜0.05),while the GW group was relatively reduced.The expression level of PPAR-gamma mRNA in the ROS group detected by fluorescent quantitative PCR was significantly up-regulated(P＜0.05),while which in the GW group was down-regulated compared with the I/R group and ROS group(P＜0.05).The expression of PPAR-gamma protein was similar to that of PPAR-gamma mRNA.Conclusion Up-regulation of myocardial PPAR-gamma expression may increase the occurrence of reperfusion arrhythmias in myocardial I/R animal model.
ABSTRACT
Objective To investigate the effects of peroxisome proliferator activated receptor gamma (PPARγ) on malignant arrhythmia in myocardial of ischemia/reperfusion(I/R) rats. Methods Twenty-four SD rats were randomly divided into four groups:Sham group, I/R group, rosiglitazone (ROS) group and PPARγ inhibitor GW9662 (GW) group. The myocardial I/R injury was induced by ligation of the left anterior descending coronary artery, with ischemia for 30 min and reperfusion for 2 h. The whole process limb Ⅱ lead electrocardiogram was applied to observe the frequency of malignant arrhythmia and record the corrected changes of QT(QTc) interval. RT-PCR was used to detect the expression of PPARγ mRNA. Results There were 5 cases of malignant arrhythmia in ROS group, 2 in I/R and 1 in GW group, 0 was found in Sham group. There was a prolongation of the QTc interval in ROS group than the other groups after ischemic stage (P＜0.05). Compared with I/R group and ROS group, the QTc intervals were shorten in ischemia 30 min and reperfusion process in GW group (P＜0.05). Compared with sham group, the expression of PPARγ mRNA was significantly increased in other three groups (P＜0.05). The expression level of PPARγ mRNA was the highest in ROS group. The expression level of PPARγ mRNA was reduced in GW group compared with that of I/R group and ROS group (P＜0.05). Conclusion Over expression of PPARγ may lead to the occurrence of malignant arrhythmia in myocardial ischemia/reperfusion rats.
ABSTRACT
Objective To investigate the relationship of serum levels of homocysteine, cystain C and uric acid with ca?rotid atherosclerosis in H-type hypertension patients. Methods A total of 132 H-type hypertension patients were collected to be studied. Their carotid intima-media thickness (IMT) was measured by Doppler ultrasonography. And according to the result of carotid artery atherosclerosis, all patients were divided into normal cIMT group (n=40),thickened cIMT group (n=43) and plague formation group (n=49). Their serum Hcy, Cyst-C, UA, blood glucose, blood lipid, blood urea nitrogen and se?rum creatinine were compared among three group and their relationship with cIMT were analyzed. Logistic regression was used to screen risk factors for carotid atherosclerosis. Results There was no significant difference in serum levels of blood glucose,blood urea nitrogen, creatinine, serum creatinine (Scr), triglyceride (TG), total cholesterol (TC), low density lipppro?tein cholesterol (LDL-c) among these three groups (P>0.05). The level of high-density lipoprotein (HDL-c) in thickened cIMT group was higher than that in plague formation group, and lower than normal cIMT group, while both serum levels of Cyst-c and UA were lower in thickened cIMT group than those in plague formation group but higher than those in normal cIMT group (P<0.05). In addition, serum level of Hcy in normal cIMT group was higher than that in thickened cIMT group and plague formation group. The cIMT grade was positively correlated with serum levels of Hcy, Cyst-C and UA (r=0.26, 0.30, 0.23, P<0.05), but was negative correlated with HDL-c(r=-0.38, P<0.05). Further more, Logistic regression analy?sis showed that Hcy,Cyst-C and UA were independent risk factors for cIMT. Conclusion Serum levels of Hcy, Cyst-C and UA are closely related to the cIMT,which indicates that they are independent risk factors of cIMT and may be used as mark?ers in judging the developments and preventions of arteriosclerosis.