Effects of catestatin on calcium handling abnormalities and ventricular arrhythmia after myocardial infarction in rats |
| |
| Authors: | LIU Tao SHI Shao-bo HUANG Yan YANG An-kang LIANG Sa WANG Teng HU Dan |
| |
| Institution: | Department of Cardiology, Renmin Hospital of Wuhan University, Cardiovascular Research Institute of Wuhan University, Hubei Key Laboratory of Cardiology, Wuhan 430060, China |
| |
| Abstract: | AIM: To determine the effects of catestatin (CST) on calcium handling abnormalities and ventri-cular arrhythmia (VA) after myocardial infarction (MI) in rats. METHODS: The adult male SD rats (n=85) were randomly divided into sham group (n=20) and operation group (n=65). MI was induced by ligation of the left anterior descending coronary artery in operation group. The rats in sham group underwent pericardiotomy but without ligating the artery. The rats survived for 1 week after operation were randomly assigned to MI group and CST group. The rats in CST group was treated with CST (30 mg·kg-1·d-1, intraperitoneal administration) for 4 weeks, while saline was applied to the rats in sham group and MI group. The calcium imaging study was performed by loading isolated ventricular cardiomyocytes with Fura-2 AM. In the whole Langendorff-perfused hearts, the programmed electrical stimulation was used to induce action potential duration (APD) alternans and VA. The protein levels of ryanodine receptor 2 (RyR2), phosphorylated RyR2 (p-RyR2), calcium/calmodulin-dependent protein kinase II (CaMKII) and phosphorylated CaMKII (p-CAMKII) were determined by Western blot. RESULTS: Compared with sham group, the protein levels of p-RyR2 and p-CaMKII, the diastolic intracellular Ca2+ concentrations and the inducibility of VA were significantly increased, whereas the thresholds of Ca2+ transient (CaT) and APD alternans and the CaT amplitude were markedly decreased in MI group (P<0.01). Compared with MI group, the protein levels of p-RyR2 and p-CaMKII, the diastolic intracellular Ca2+ concentration and the inducibility of VA were significantly decreased, while the thresholds of CaT and APD alternans and the CaT amplitude were markedly increased in CST group (P<0.01). No significant difference of the protein expression of RyR2 and CaMKII among the 3 groups was observed (P>0.05). CONCLUSION: CST reduces the susceptibility to VA after MI via preventing calcium handling abnormalities. |
| |
| Keywords: | Myocardial infarction Catestatin Calcium handling Ventricular arrhythmia |
|
| 点击此处可从《园艺学报》浏览原始摘要信息 |
| 点击此处可从《园艺学报》下载免费的PDF全文 |
|
