[Relationship between M3 receptor and myocyte apoptosis induced by acute myocardial infarction].
OBJECTIVE
To explore the effects of M3 receptor on myocyte apoptosis induced by acute myocardial infarction in rats.


METHODS
Rat model was induced by ligation of the anterior branch of the left coronary artery. All animals were divided into four groups: sham-operated group, occlusion group, choline group (10 mg x kg(-1), iv), and 4DAMP (4-diphenylacetoxy-N-methylpiperidine-methiodide) group (0.12 mg x kg(-1), iv). The serum malondialdehyde (MDA) content and superoxide dismutase (SOD) activity were determined. The infarct size areas on the myocardium were identified by TTC staining. The apoptosis in cardiomyocyte was detected by TUNEL assay and apoptosis-related proteins in Bcl-2 and Fas expression were measured by immunohistochemistry assay.


RESULTS
M3 receptor agonist choline reduced serum MDA content and increased SOD activity. The myocardial expression of Bcl-2 was increased, whereas the expression of Fas was decreased by choline. However, blockade of M3 receptor by 4DAMP completely inhibited these effects of choline on cardiac myocytes.


CONCLUSIONS
Activation of M3 receptor has protective effect on myocyte apoptosis induced by acute myocardial infarction in rat, and this effect might be related to modulating the expression of some immediateearly genes including Bcl-2 and Fas.
Liu
Yan
Y
Department of Pharmacology, Harbin Medical University, China.
Jing
Yu-hong
YH
Sun
Hong-li
HL
Li
Hu-lun
HL
Yang
Bao-feng
BF
D000818:Animals; D017209:Apoptosis; D002794:Choline / Q000494:pharmacology; D008297:Male; D008315:Malondialdehyde / Q000097:blood; D009203:Myocardial Infarction / Q000378:metabolism / Q000473:pathology*; D009206:Myocardium / Q000473:pathology; D032383:Myocytes, Cardiac / Q000378:metabolism / Q000473:pathology*; D010880:Piperidines / Q000494:pharmacology; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D043587:Receptor, Muscarinic M3 / Q000819:agonists / Q000037:antagonists & inhibitors; D018124:Receptors, Tumor Necrosis Factor / Q000378:metabolism; D013482:Superoxide Dismutase / Q000097:blood; D019014:fas Receptor
C491898:Fas protein, rat; D010880:Piperidines; D019253:Proto-Oncogene Proteins c-bcl-2; D043587:Receptor, Muscarinic M3; D018124:Receptors, Tumor Necrosis Factor; D019014:fas Receptor; D008315:Malondialdehyde; C042375:4-diphenylacetoxy-1,1-dimethylpiperidinium; D013482:Superoxide Dismutase; D002794:Choline