The experimental study on reinnervation of acetylcholinesterase positive nerves after acute myocardial infarction

Objective: To observe the reinnervation of acetylcholinesterase positive nerves(AChE) in the viable peri-infarct zones after acute myocardial infarction(AMI). Methods: The Wistar rats were used in this study. Left anterior decending coronary artery was ligated to form AMI. Hearts were excised 1, 2, 12 weeks after AMI. Karnovsky-Roots methods of histochemical techniques and electron microscopy were used to show the distribution of AChE positive nerves, while the density of AChE positive nerves was calculated by Medical Image Analysis Processing System. Results: The density of AChE positive nerves of viable peri-infarct zones decreased 1 and 2 weeks after AMI, however, the density of AChE positive nerves at same area increased obviously 12 weeks after AMI, and there were no statistical difference comparing it with control group. Under electron microscopy, AChE positive axons colored strongly showed scattered granules located within the intermuscular nerve fibers. Conclusions: Reinnervation appears in the viable peri-infarcted zone of myocardium 12 weeks after AMI.