Background Connexin43 （Cx43） is the predominant gap junction protein in heart and is involved in the control of cell-to-cell communication to modulate the contractility and the electrical coupling of cardiac myocyte...Background Connexin43 （Cx43） is the predominant gap junction protein in heart and is involved in the control of cell-to-cell communication to modulate the contractility and the electrical coupling of cardiac myocytes. Left ventricular （LV） hypertrophy is accompanied by changes of Cx43 expression. Recent studies have demonstrated that statins reduced cardiac hypertrophy. However, it is unknown whether statins can affect Cx43 expression in hypertrophied left ventricular myocardium. This study was designed to assess the effects of atorvastatin on LV hypertrophy and Cx43 expression in spontaneously hypertensive rats （SHR）. Methods Nine-week old SHRs were randomly divided into two groups. Some received atorvastatin at 30 mg/kg by oral gavage once daily for 8 weeks （SHR-A）; others received vehicle. Age-matched Wistar-Kyoto rats （WKY） received atorvastatin or vehicle for 8 weeks were used as controls. At the end of the experiment, we investigated LV hypertrophy and the expression of Cx43 in LV myocardium in four groups. Cx43 expression was investigated by the methods of Western blotting, immunohistochemistry, and transmission electron microscope. LV hypertrophy was accessed by pathological analysis and plasma brain natriuretic peptide （BNP） level. Results LV hypertrophy was prominent in untreated SHR. In SHR, LV myocardium Cx43 level was upregulated, and the distribution of Cx43 was displaced from their usual locations to other sites at various distances away from the intercalated disks. After atorvastatin treatment, myocardium Cx43 level was reduced in SHR-A, and the distribution of Cx43 gap junction became much regular and confined to intercalated disk. Statins also prevented LV hypertrophy in SHR. Conclusions These results provide novel in vivo evidence for the key role of Cx43 gap junctions in LV hypertrophy and the possible mechanism in anti-hypertrophic effect of statins. Atorvastatin treatment may have beneficial effects on LV hypertrophy in spontaneously hypertensive rats.展开更多
To observe the effects of different acupuncture manipulations on blood pressure and target organ damage in spontaneously hypertensive rats（SHRs）, this study used the reinforcing twirling method（1.5–2-mm depth; rot...To observe the effects of different acupuncture manipulations on blood pressure and target organ damage in spontaneously hypertensive rats（SHRs）, this study used the reinforcing twirling method（1.5–2-mm depth; rotating needle clockwise for 360° and then counter clockwise for 360°, with the thumb moving heavily forward and gently backward, 60 times per minute for 1 minute, and retaining needle for 9 minutes）, the reducing twirling method（1.5–2-mm depth; rotating needle counter clockwise for 360° and then clockwise for 360°, with the thumb moving heavily backward and gently forward, 60 times per minute for 1 minute, and retaining needle for 9 minutes）, and the needle retaining method（1.5–2-mm depth and retaining the needle for 10 minutes）. Bilateral Taichong（LR3） was treated by acupuncture using different manipulations and manual stimulation. Reinforcing twirling, reducing twirling, and needle retaining resulted in a decreased number of apoptotic cells, reduced Bax m RNA and protein expression, and an increased Bcl-2/Bax ratio in the hippocampus compared with the SHR group. Among these groups, the Bcl-2/Bax protein ratio was highest in the reducing twirling group, and the Bcl-2/Bax m RNA ratio was highest in the needle retaining group. These results suggest that reinforcing twirling, reducing twirling, and needle retaining methods all improve blood pressure and prevent target organ damage by increasing the hippocampal Bcl-2/Bax ratio and inhibiting cell apoptosis in the hippocampus in SHR.展开更多
基金This work was supported by the Science and Technology Committee of Zhejiang Province(No.021107057)the Natural Science Foundation of Zhejiang Province(No.M303874).
基金grants from Science and Technology Foundation of Zhejiang Province (No. 021107613)Health Science Research Foundation of Zhejiang Province (No. 2003A043)
文摘Background Connexin43 （Cx43） is the predominant gap junction protein in heart and is involved in the control of cell-to-cell communication to modulate the contractility and the electrical coupling of cardiac myocytes. Left ventricular （LV） hypertrophy is accompanied by changes of Cx43 expression. Recent studies have demonstrated that statins reduced cardiac hypertrophy. However, it is unknown whether statins can affect Cx43 expression in hypertrophied left ventricular myocardium. This study was designed to assess the effects of atorvastatin on LV hypertrophy and Cx43 expression in spontaneously hypertensive rats （SHR）. Methods Nine-week old SHRs were randomly divided into two groups. Some received atorvastatin at 30 mg/kg by oral gavage once daily for 8 weeks （SHR-A）; others received vehicle. Age-matched Wistar-Kyoto rats （WKY） received atorvastatin or vehicle for 8 weeks were used as controls. At the end of the experiment, we investigated LV hypertrophy and the expression of Cx43 in LV myocardium in four groups. Cx43 expression was investigated by the methods of Western blotting, immunohistochemistry, and transmission electron microscope. LV hypertrophy was accessed by pathological analysis and plasma brain natriuretic peptide （BNP） level. Results LV hypertrophy was prominent in untreated SHR. In SHR, LV myocardium Cx43 level was upregulated, and the distribution of Cx43 was displaced from their usual locations to other sites at various distances away from the intercalated disks. After atorvastatin treatment, myocardium Cx43 level was reduced in SHR-A, and the distribution of Cx43 gap junction became much regular and confined to intercalated disk. Statins also prevented LV hypertrophy in SHR. Conclusions These results provide novel in vivo evidence for the key role of Cx43 gap junctions in LV hypertrophy and the possible mechanism in anti-hypertrophic effect of statins. Atorvastatin treatment may have beneficial effects on LV hypertrophy in spontaneously hypertensive rats.
基金supported by the National Natural Science Foundation of China,No.81072861,81373727
文摘To observe the effects of different acupuncture manipulations on blood pressure and target organ damage in spontaneously hypertensive rats（SHRs）, this study used the reinforcing twirling method（1.5–2-mm depth; rotating needle clockwise for 360° and then counter clockwise for 360°, with the thumb moving heavily forward and gently backward, 60 times per minute for 1 minute, and retaining needle for 9 minutes）, the reducing twirling method（1.5–2-mm depth; rotating needle counter clockwise for 360° and then clockwise for 360°, with the thumb moving heavily backward and gently forward, 60 times per minute for 1 minute, and retaining needle for 9 minutes）, and the needle retaining method（1.5–2-mm depth and retaining the needle for 10 minutes）. Bilateral Taichong（LR3） was treated by acupuncture using different manipulations and manual stimulation. Reinforcing twirling, reducing twirling, and needle retaining resulted in a decreased number of apoptotic cells, reduced Bax m RNA and protein expression, and an increased Bcl-2/Bax ratio in the hippocampus compared with the SHR group. Among these groups, the Bcl-2/Bax protein ratio was highest in the reducing twirling group, and the Bcl-2/Bax m RNA ratio was highest in the needle retaining group. These results suggest that reinforcing twirling, reducing twirling, and needle retaining methods all improve blood pressure and prevent target organ damage by increasing the hippocampal Bcl-2/Bax ratio and inhibiting cell apoptosis in the hippocampus in SHR.
