Myocardial angiogenesis after chronic ghrelin treatment in a rat myocardial infarction model

Abstract Ghrelin has a protective role in a rat model of myocardial infarction (MI), but the underlying mechanism is not clear. Here, we investigated the effects of ghrelin treatment on angiogenesis in an experimental rat MI model. Adult male Sprague–Dawley rats were subjected to MI by ligating the anterior descending coronary artery. The rats were then treated with a subcutaneous injection of ghrelin (100 μg/kg) or saline (control group) for 4 weeks. Sham animals underwent thoracotomy and pericardiotomy, but not LAD ligation. At 28 days after ligation, the ghrelin treatment group showed a higher density of α-SMA positive vessels than the saline treatment MI group in myocardial infarct (6 ± 2.1/mm 2 vs 4 ± 1.8/mm 2 , P  2 vs 15 ± 5.7/mm 2 , P