Study On The Calcium Abnormalities In Coronary Arterial Smooth Muscle Cells During Heart Failure

Objective: To investigate the abnormal calcium clearance and reactive oxygen species production in coronary artery smooth muscle cells of the individual with heart failure.Methods:1 30 adult male SD rats were randomly divided into two groups: sham-operated group(n=10),heart failure group(n =20).Heart failure model was established through ligation of left anterior descending coronary artery.The left anterior descending coronary artery was only exposed without ligation in sham-operated group rats. After 12 weeks, 10 heart failure rats were selected randomly. Ischemic and non-ischemic coronary artery blood vessels were taken respectively.2 A single coronary artery vascular smooth muscle cell was obtained using the two-step enzyme(papain and collagenase)separation method.3 The coronary artery vascular smooth muscle cells were identified by immunoflourescent technique.4 The calcium concentration and reactive oxygen species production were measured by flow cytometry.5 The expression level of p47 phox,p-p47 phox,SERCA and NCX were measured by the western blot method.6 q RT-PCR were used to detect the m RNA expression of p47 phox,p- p47 phox, SERCA and NCX.Results :1 The cells identified by immunoflourescent technique were smooth muscle cells.2 The level of calcium and reactive oxygen species in HF group(Non-ischemic areas) and HF group(ischemic areas) was significantly increased compared with sham group(p<0.01).There was no significant difference in calcium level and reactive oxygen species level between the two HF groups(p >0.05).3 The expression of p47 phox,p-p47 phox in HF group(Non-ischemic areas) and HF group(ischemic areas) were significantly up-regulated compared with sham group(p<0.05). The expression of NCX in HF group(Non-ischemic areas) and HF group(ischemic areas) were significantly up-regulated compared with sham group(p <0.01). The expression of SERCA in HF group(Non-ischemic areas) and HF group(ischemic areas) were significantly decreased compared with sham group(p <0.01). There was no significant difference in the expression of p47 phox,p-p47 phox,NCX and SERCA between the two HF groups(p >0.05).4 The m RNA expression of p47 phox,NCX in HF group(Non-ischemic areas) and HF group(ischemic areas) were significantly up-regulated compared with sham group.The m RNA expression of SERCA in HF group(Non-ischemic areas) and HF group(ischemic areas) were significantly decreased compared with sham group.There was no significant difference in the m RNA expression of p47 phox, NCX, SERCA between the two HF groups.Conclusion:1 The increased calcium ion concentration in coronary artery vascular smooth muscle cells(Non-ischemic areas and ischemic areas) during heart failure could contribute to vasodilation dysfunction,vasospasm and even heart failure.2 The excessive production of ROS in coronary artery vascular smooth muscle cells(Nonischemic areas and ischemic areas) during heart failure could lead to increased hardness of blood vessels and even heart failure.3 The increased NCX and reduced SERCA during heart failure could cause abnormal calcium clearance.4 The phosphorylation of p47 phox during heart failure could cause increased ROS productin and affect calcium homeostasis.