Objective: To study the changes of oxygen free radical, expression of apoptotic gene, ultrastructure of myocardial cell and second injury of the heart following the intestinal ischemia and reperfusion. Methods: Making...Objective: To study the changes of oxygen free radical, expression of apoptotic gene, ultrastructure of myocardial cell and second injury of the heart following the intestinal ischemia and reperfusion. Methods: Making the models of ischemia and reperfusion by clamping superior mesenteric artery, the concentration of NO and SOD in the blood was examined before clamping the artery and reperfusion for 0, 30, 60 min, 1, 3, and 7 d. The expression of Bax, Bal-2, and p53 in myocardial cell was studied by means of immunohistochemical SP method and the microstructure damage was observed under electron microscopy. Results: After clamping the superior mesenteric artery and reperfusion the concentration of NO increased continuously and reached a peak for reperfusion 7 d (P<0.01) but that of SOD decreased from 30 min to 7 d. The expression of Bax, p53 and Bcl-2 also increased obviously especially for reperfusion 30 min and 7 d following ischemia and reperfusion. After reperfusion for 30 min the positive cell rate of Bax, p53 and Bcl-2 was 53.6%, 45.9% and 67.9%, for reperfusion 7 d it was 52.4%, 43.4% and 31.9% respectively, but the positive cell rate of Bax and p53 was higher than that of Bcl-2. The result of electron microscopy observation showed mfofiliments breaked, dissolved and chromatin condensed. Conclusion: Intestinal ischemia and reperfusion of rat can induced the changes of oxygen free radical and the expression of apoptotic gene and second injury of myocardial cells.展开更多
OBJECTIVE: To investigate the underlying mechanism of reduced myocardial ischemia-reperfusion (I/R) injury in rats using the traditionalTibetan medicine Sanweitanxiang powder (SWTX). METHODS: Rats were randomly divide...OBJECTIVE: To investigate the underlying mechanism of reduced myocardial ischemia-reperfusion (I/R) injury in rats using the traditionalTibetan medicine Sanweitanxiang powder (SWTX). METHODS: Rats were randomly divided into six groups (n=10) as follows: (a) propranolol dinitrate control group, given propranolol dinitrate 0.02 g/kg for 10 days before I/R, (b) SWTX with a high dose group, given SWTX 1.5 g/kg for 10 days before I/R, (c) SWTX with a medium dose group, given SWTX 1.25 g/kg for 10 days before I/R, (d) sham group (Sham), in which the rat heart was exposed by pericardiotomy but without I/R, (e) SWTX with a low dose group, given SWTX 1.0 g/kg for 10 days before I/R, and (f) I/R injury group. Rats were intragastrically pretreated with propranolol dinitrate orSWTX. After that, the operation to cause ischemia and reperfusion was conducted.The histopathologic changes of rat hearts were observed by hematoxylin and eosin staining and transmission electron microscopy. Ca2+ homeostasis protein expression was determined by western blot. RESULTS: After SWTX pretreatment, the development of ultrastructural pathological changes from IR injury was attenuated. A decrease in the expression of B-cell lymphoma 2 associated X protein, and an increase in the expression of B-cell lymphoma 2 were observed. An increased activation of extracellular signal regulated kinases were found. Compared with the sham group, the expression of sarcoplasmic reticulum calcium-ATPase, phospholamban, and calsequestrin were all up-regulated after pretreatment with SWTX. CONCLUSION: The protective mechanism of SWTX pretreatment on myocardial I/R injury might be related to its effect on maintaining the balance of calcium homeostasis in rat heart.展开更多
文摘Objective: To study the changes of oxygen free radical, expression of apoptotic gene, ultrastructure of myocardial cell and second injury of the heart following the intestinal ischemia and reperfusion. Methods: Making the models of ischemia and reperfusion by clamping superior mesenteric artery, the concentration of NO and SOD in the blood was examined before clamping the artery and reperfusion for 0, 30, 60 min, 1, 3, and 7 d. The expression of Bax, Bal-2, and p53 in myocardial cell was studied by means of immunohistochemical SP method and the microstructure damage was observed under electron microscopy. Results: After clamping the superior mesenteric artery and reperfusion the concentration of NO increased continuously and reached a peak for reperfusion 7 d (P<0.01) but that of SOD decreased from 30 min to 7 d. The expression of Bax, p53 and Bcl-2 also increased obviously especially for reperfusion 30 min and 7 d following ischemia and reperfusion. After reperfusion for 30 min the positive cell rate of Bax, p53 and Bcl-2 was 53.6%, 45.9% and 67.9%, for reperfusion 7 d it was 52.4%, 43.4% and 31.9% respectively, but the positive cell rate of Bax and p53 was higher than that of Bcl-2. The result of electron microscopy observation showed mfofiliments breaked, dissolved and chromatin condensed. Conclusion: Intestinal ischemia and reperfusion of rat can induced the changes of oxygen free radical and the expression of apoptotic gene and second injury of myocardial cells.
基金Supported by a Grant from the National Natural Sciences Foundation of China(No.81060368)
文摘OBJECTIVE: To investigate the underlying mechanism of reduced myocardial ischemia-reperfusion (I/R) injury in rats using the traditionalTibetan medicine Sanweitanxiang powder (SWTX). METHODS: Rats were randomly divided into six groups (n=10) as follows: (a) propranolol dinitrate control group, given propranolol dinitrate 0.02 g/kg for 10 days before I/R, (b) SWTX with a high dose group, given SWTX 1.5 g/kg for 10 days before I/R, (c) SWTX with a medium dose group, given SWTX 1.25 g/kg for 10 days before I/R, (d) sham group (Sham), in which the rat heart was exposed by pericardiotomy but without I/R, (e) SWTX with a low dose group, given SWTX 1.0 g/kg for 10 days before I/R, and (f) I/R injury group. Rats were intragastrically pretreated with propranolol dinitrate orSWTX. After that, the operation to cause ischemia and reperfusion was conducted.The histopathologic changes of rat hearts were observed by hematoxylin and eosin staining and transmission electron microscopy. Ca2+ homeostasis protein expression was determined by western blot. RESULTS: After SWTX pretreatment, the development of ultrastructural pathological changes from IR injury was attenuated. A decrease in the expression of B-cell lymphoma 2 associated X protein, and an increase in the expression of B-cell lymphoma 2 were observed. An increased activation of extracellular signal regulated kinases were found. Compared with the sham group, the expression of sarcoplasmic reticulum calcium-ATPase, phospholamban, and calsequestrin were all up-regulated after pretreatment with SWTX. CONCLUSION: The protective mechanism of SWTX pretreatment on myocardial I/R injury might be related to its effect on maintaining the balance of calcium homeostasis in rat heart.
