Objective: To investigate the possibility that skeletal muscle satellite cells implanted into injured myocardium in different time after myocardial infarction differntiate into cardiac-like muscle fibers, thus repairing the damaged heart muscle.
Methods: Coronary ligation combined with C-shape cryoinjury was performed upon 16 dogs to make a myocardial infarction (MI) area I on left ventricular free wall and an area II was made by cryoinjury near MI area I. Then the dogs were divided into two groups, 8 in each group. In group A the satellite cells (6 x 10(7)) labeled with Diamidino-phenyl-indole (DAPI) were collected and resuspended in 5 ml of M199 and then were injected into the two. MI areas of the same donor dogs through the coronary artery and heart wall. In group B, the collected satellite cells (6 x 10(7)) were implanted into the two MI areas in the same way under second thoracotomy 10 approximately 14 days after myocardial infarction was caused. Four weeks after implantation the dogs were sacrificed under general anesthesia. The heart specimens were processed for histological examination.
Results: Small area of MI was successfully made by combination of coronary ligation and C-shape cryoinjury or by pure cryoinjury. Discrete fluorescence could be seen in the MI area I of group A under fluorescent microscope, however, no fluorescence was seen in the MI area I of group B. Line-shaped fluorescence was found in the MI area II of both groups under fluorescent microscope. No striated muscle was found by light microscope and transmission electron microscope.
Conclusion: Cellular cardiomyoplasty with satellite cell implantation is still immature for clinical use now. Further research must be done in the future.