Effect of chronic psychological stress on vascular endothelial dysfunction rats and intervention tongxinluo on it / 中国中西医结合杂志

<p><b>OBJECTIVE</b>To observe the effect of chronic psychological stress on vascular endothelial dysfunction rats and to explore the intervention and mechanism of Tongxinluo (TXL) on it.</p><p><b>METHODS</b>Forty male Wistar rats were randomly divided into the normal control group (with no modeling), the endothelial dysfunction group (the HCY group), the psychological stress group (the model group), and TXL group, ten in each group. Rats in the latter three groups were fed with 3% high methionine diet to duplicate vascular endothelial dysfunction (VED) model. In addition, chronic psychological stress was applied in VED rats using repeated binding method. TXL at the dose of 1.2 g/kg body weight was given by gastrogavage. The plasma endothelin (ET) and angiotensin II (Ang II), serum cortisone (CORT) were detected by radioimmunoassay. The serum nitric oxide (NO) was detected by nitrate reductase. Ultrastructural changes of aortic endothelial cells were observed by transmission electron microscope. Serum levels of norepinephrine (NE) and epinephrine (E) were detected by enzyme linked immunosorbent assay (ELISA).</p><p><b>RESULTS</b>Compared with the plasma ET level and the serum NO level in the HCY group (161.70 +/- 13.96 pg/mL and 26.82 +/- 13.03 micromol/L), the plasma ET level obviously increased (178.25 +/- 21.85 pg/mL) (P < 0.05) and the serum NO level decreased (24.91 +/- 9.95 micromol/L, P > 0.05), levels of CORT, NE, and E obviously increased in the model group (all P < 0.05). Ultrastructural changes of aortic endothelial cells were obviously injured. Compared with the model group, the plasma ET level (154.74 +/- 13.27 pg/mL), Ang II, CORT, NE, and E obviously decreased (P < 0.05, P < 0.01), the serum NO level obviously increased (34.44 +/- 18.35 micromol/L, P < 0.05). Ultrastructural changes of aortic endothelial cells were obviously improved.</p><p><b>CONCLUSIONS</b>Chronic psychological stress could obviously aggravate endothelial injury in VED rats. TXL showed protection on the vascular endothelial structure and function.</p>

Effects of Tongxinluo on neuron ultrastructure and endothelial cell self-repairing ability in hypoxia preconditioning mice / 中国应用生理学杂志

<p><b>OBJECTIVE</b>To observe the ultrastructure changes of cerebral cortex neuron and endothelial cell in hypoxia preconditioning mice and the effects of Tongxinluo (TXL, Chinese traditional medilihe) on them.</p><p><b>METHODS</b>Mice were randomly divided into 4 groups: control group, hypoxia group, hypoxia preconditioning (HP) group and Tongxinluo (TXL) group. The hypoxia preconditioning mice were exposed by repetitive hypoxia for 5 runs. The animal's tolerance time of each hypoxia run was recorded. The ultrastructure change of cerebral neuron and endothelial cell were studied by electron microscope.</p><p><b>RESULTS</b>The hypoxic tolerance time in HP and TXL groups were significantly increased run by run. Compared with HP group, the tolerance time of TXL group were increased in every run. The ultrastructure of cerebral neuron and endothelial cell in hypoxia group changed obviously, mitochondrion and endoplasmic reticulum destroyed. However they were slighter in HP group than those in hypoxia group. The change in TXL group had no obvious differentce with control group and were slighter than those in HP group.</p><p><b>CONCLUSION</b>Hypoxia preconditioning shows that organism has a strong self-repairing ability. Tongxinluo self-repairing; could increase self-repairing ability and adaptive ability of mice to hypoxia obviously.</p>

Effects of Chinese herbs on multiple ion channels in isolated ventricular myocytes / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Shensong Yangxin (SSYX) is one of the compound recipe of Chinese materia medica. This study was conducted to investigate the effects of SSYX on sodium current (I(Na)), L-type calcium current (I(Ca, L)), transient outward potassium current (I(to)), delayed rectifier current (I(K)), and inward rectifier potassium currents (I(K1)) in isolated ventricular myocytes.</p><p><b>METHODS</b>Whole cell patch-clamp technique was used to study ion channel currents in enzymatically isolated guinea pig or rat ventricular myocytes.</p><p><b>RESULTS</b>SSYX decreased peak I(Na) by (44.84 +/- 7.65)% from 27.21 +/- 5.35 to 14.88 +/- 2.75 pA/pF (n = 5, P < 0.05). The medicine significantly inhibited the I(Ca, L). At concentrations of 0.25, 0.50, and 1.00 g/100 ml, the peak I(Ca, L) was reduced by (19.22 +/- 1.10)%, (44.82 +/- 6.50)% and (50.69 +/- 5.64)%, respectively (n = 5, all P < 0.05). SSYX lifted the I - V curve of both I(Na) and I(Ca, L) without changing the threshold, peak and reversal potentials. At the concentration of 0.5%, the drug blocked the transient component of I(to) by 50.60% at membrane voltage of 60 mV and negatively shifted the inactive curve and delayed the recovery from channel inactivation. The tail current density of I(K) was decreased by (30.77 +/- 1.11)% (n = 5, P < 0.05) at membrane voltage of 50 mV after exposure to the medicine and the time-dependent activity of I(K) was also inhibited. Similar to the effect on I(K), the SSYX inhibited I(K1) by 33.10% at the test potential of -100 mV with little effect on reversal potential and the rectification property.</p><p><b>CONCLUSIONS</b>The experiments revealed that SSYX could block multiple ion channels such as I(Na) I(Ca, L), I(k), I(to) and I(K1), which may change the action potential duration and contribute to some of its antiarrhythmic effects.</p>

Remote postconditioning by brief renal ischemia and reperfusion reduces acute myocardial ischemia and reperfusion induced myocardial apoptosis in rabbits / 中华心血管病杂志

<p><b>OBJECTIVES</b>To observe the effects of renal ischemic postconditioning (RI-Post) on myocardial apoptosis in rabbits with acute myocardial ischemia and reperfusion.</p><p><b>METHODS</b>All rabbits were subjected to 60 minutes ischemia by left anterior descending coronary artery occlusion (LADO) and 6 hours reperfusion. The rabbits are randomly divided into 3 groups (n = 8 in each group): (1) Ischemia-reperfusion (IR): LADO and reperfusion without additional intervention; (2) RI-Post: after 60 minutes of LADO, the left renal artery was occluded for 30 seconds and reperfused for 30 seconds and repeated 3 times, then the coronary artery was reperfused for 6 hours; (3) Medication intervention (MI): 10 minutes before coronary reperfusion, rabbits were treated with PKC antagonist GF109203X (0.05 mg/kg, IV), followed by RI-Post treatment and 6 hours coronary reperfusion. Myocardial apoptosis was measured by TUNEL and the myocardial Bcl-2 and Bax protein expressions were assessed by immunohistochemistry.</p><p><b>RESULTS</b>Compared with the IR group and the MI group, myocardial apoptosis was significantly reduced (P < 0.05) and the Bcl-2 protein expression increased (P < 0.01) while the Bax protein expression decreased (P < 0.05) in the RI-Post group.</p><p><b>CONCLUSIONS</b>Remote renal postconditioning applied right before the onset of coronary artery reperfusion can reduce the myocardial apoptosis induced by myocardial ischemia and reperfusion and up-regulate Bcl-2 while down-regulate Bax expression possibly by activation of protein kinase C.</p>

Determination of sildenafil citrate content by capillary zone electrophoresis / 第二军医大学学报

Objective: To establish capillary zone electrophoresis method for determination of sildenafil citrate (Viagra) content in its troche. Methods： Using tetrandrine as internal standard(IS), the electrophoretic separation was achieved with 25 mmol/L borate (pH=7.89) running buffer. And a voltage of 14 kV was applied to the 40 cm×75 μm(i.d) capillary. The analytes were introduced into capillary by siphon (1 s) and determined with on-column monitoring at 214 nm. Results：The determination could be completed within 4 min and the minimum concentration of detection was 5 μg/ml.The analytical results of sildenafil citrate samples demonstrated a good linear relationship within the range of 24-480 μg/ml.The relative standard deviations (RSD) of intra-day was less than 1.58% and that of inter-day was less than 2.46%.The present recoveries were between 95%-105％. Conclusion：The CZE method is accurate, simple, rapid and reliable, so it can be applied to the determination of sildenafil citrate content.

Determination of sildenafil citrate content by capillary zone electrophoresis / 第二军医大学学报

Objective: To establish capillary zone electrophoresis method for determination of sildenafil citrate (Viagra) content in its troche. Methods： Using tetrandrine as internal standard(IS), the electrophoretic separation was achieved with 25 mmol/L borate (pH=7.89) running buffer. And a voltage of 14 kV was applied to the 40 cm×75 μm(i.d) capillary. The analytes were introduced into capillary by siphon (1 s) and determined with on-column monitoring at 214 nm. Results：The determination could be completed within 4 min and the minimum concentration of detection was 5 μg/ml.The analytical results of sildenafil citrate samples demonstrated a good linear relationship within the range of 24-480 μg/ml.The relative standard deviations (RSD) of intra-day was less than 1.58% and that of inter-day was less than 2.46%.The present recoveries were between 95%-105％. Conclusion：The CZE method is accurate, simple, rapid and reliable, so it can be applied to the determination of sildenafil citrate content.