[Significance of plasma 8-iso-prostaglandin F2alpha level in acute myocardial ischemia and intervention effect of N-acetylcysteine: a study in rats].
OBJECTIVE
To examine the correlation between 8-iso-prostaglandin F2alpha (8-iso-PGF2alpha) levels in the plasma and myocardial tissue of rats with myocardial ischemia and observe the intervention effect of N-acetylcysteine (NAC), for the purpose of assessing the value of 8-iso-PGF2alpha in estimating the extent of free radical damage and implementing possible interventions.


METHODS
Forty-five Wistar rats were divided into ischemia, ischemia+NAC and control groups, and in the former 2 groups, acute myocardial ischemia models were produced by pituitrin. Elevated ST segment in ECG served as the indicator for myocardial ischemia. Rats in ischemia+NAC group were pre-treated with NAC (0.1 g/kg x d) for three weeks before the ischemia 8-iso-PGF2alpha levels in the plasma and myocardial tissue were determined by enzyme-linked immunosorbent assay (ELISA).


RESULTS
In ischemia group, the 8-iso-PGF2alpha levels in the plasma and myocardial tissue were 187.4+/-45.8 pg/ml and 259.3+/-47.5 pg/g, respectively, higher than those in the control group (60.4+/-13.7 pg/ml and 88.6+/-16.9 pg/g, respectively, P<0.01) and those in ischemia+NAC group (88.2+/-16.4 pg/ml and 109.4+/-24.7 pg/g, respectively, P<0.01). A positive correlation was noted between the 8-iso-PGF2alpha levels in the plasma and myocardial tissue (r=0.865, P<0.01). In comparison with the control group, elevation of the ST segment of ECG in rats with myocardial ischemia was obvious, and the peak elevation occurred 45 min after ischemia (0.34+/-0.05 mV, P<0.01). Pre-treatment with NAC proved to help alleviate the subsequent ischemia, with ST segment elevation of only 0.18+/-0.05 mV.


CONCLUSIONS
In condition of acute myocardial ischemia in rats, 8-iso-PGF2alpha levels tend to increase, which can be indicative of the degree of myocardial ischemia. NAC pre-treatment can alleviate the ischemic condition by offsetting the damage caused by the free radicals.
Yan
Qun-chao
QC
First Affiliated Hospital, Jinan University, Guangzhou 510632, China.
Xiong
Ai-hua
AH
Xiao
Xin
X
Luo
You-tong
YT
D000111:Acetylcysteine / Q000494:pharmacology*; D000818:Animals; D015237:Dinoprost / Q000031:analogs & derivatives*; D004562:Electrocardiography; D028441:F2-Isoprostanes / Q000032:analysis / Q000097:blood*; D008297:Male; D009203:Myocardial Infarction / Q000097:blood* / Q000503:physiopathology; D009206:Myocardium / Q000737:chemistry; D051381:Rats; D017208:Rats, Wistar
D028441:F2-Isoprostanes; C075750:8-epi-prostaglandin F2alpha; D015237:Dinoprost; D000111:Acetylcysteine