OBJECTIVE To explore the effect of chloride channels on the neuronal injury following cerebral ischemia. METHODS Tweleve day in vitro (12dIV) neurons in rats were randomly divided into normal control, 3-morpholinosydnonimine (SIN-1, 1.0 mmol·L~(-1) for 18 h) group, SIN-1+4-acetamido-4'-isothiocyanatostilbene-2,2'-disulphonic acid(SITS, 0.5 mmol·L~(-1)) group and SIN-1+4,4'-diisothiocyanatostilbene-2,2'-disulfonic acid (DIDS, 0.1 mmol·L~(-1)) group. Drugs were added with SIN-1 simultaneously and coincubated for 18 h. The neuronal apoptosis and morphological changes were detected with Hoechst 33258. Chloride channels(ClC)-2/ClC-3 were analyzed with immunofluorescence, the chloride channel currents were recorded with whole cell patch-clamp technique. RESULTS Hoechst 33258 staining showed that the apoptotic percentages were (18.61±0.59) %, (50.43±0.56)%, (23.37±0.52)% and (23.37±0.84)% in normal control group, SIN-1 group, SIN-1+SITS or SIN-1+DIDS groups, respectively. ClC-2/ClC-3 were positively expressed in normal neurons. The currents in neurons exposed to SIN-1 were increased about 55%-56%, SITS and DIDS, two kinds of chloride channel blockers could inhibited the currents about 50%-60% and 30%-40%, respectively. CONCLUSION Voltage-dependent chloride channel maybe participate in the neuronal apoptosis induced by NO, and the activities of chloride channels are perhaps involved in the cerebral ischemic injury.

Aim To observe the protective effects of SITS and DIDS,two kinds of chloride channel blockers,on hippocampal neuronal damage induced by NO in culture.Methods The cultures were divided into three groups:control group,NO treatment group,NO treatment plus chloride channel blocker group. The cultures were detected with the methods of morphological stain (Hoechst 33258),and the apoptotic neurons and neuronal viabilities were observed through MTT quantitative analysis. The activated caspase-3 was analyzed with western blot.Results There were significant protective effects of SITS and DIDS on neuronal damage with dose-dependence.Conclusions Chloride channel blockers have some protective effects against neuronal injury induced by NO.

BACKGROUND: Recent studies indicate that bone marrow messenchymal stem cells (MSCs) can repairinjured myocardium and improve cardiac functions. However, there are still no effective non-invasive methods to detect ventricular wall motion, survival status of transplanted cells, and microcirculation improvement after MSCsimplantation. OBJECTIVE: To detect the effects of MSCs implantation on the cardiac function of ischemic myoeardium and investigate changes of tissue acoustics characteristics by using integrated backscatter (IBS) and Doppler tissue imaging (DT1). DESIGN, TIME AND SETTING: Completely randomized grouping design, and randomized controlled study, which was carried out in the Department of Cardiology, Renmin Hospital of Wuhan University from December 2004 to June 2005 (important laboratory of 211 government). MATERIALS: Forty-eight male rabbits with irrespective of gender were used for study. Anti-troponin T (TnT) antibody was provided by Maxim Company, USA; anti-bromodeoxyuridine (BrdU) antibody by Sigma Company, USA; Sonos 5500 echocardiography by HP Company, USA.METHODS: Forty-eight rabbits were randomly divided into model group and implantation group. Model of myocardium infarction was created in rabbits by left anterior descending coronary artery (LAD) ligation. Three days after modeling, autologous bone marrow MSCs were injected into crossed myocardium between infarction and non-infarction regions based on 5 injected points.MAIN OUTCOME MEASURES: Indicators including ventricular size, ventricular wall thickness, and ejection fraction (EF) in the left ventricle (LV) were measured with routine echocardiography one day before myocardial infarction, two weeks after myocardial infarction, and four weeks after implantation. IBS and DTI might detect the anterior backscatter parameters (AII, or IB) and ventricular wall motion parameters (PPI, or CVIB) to calculate the average backscatter scores and backscatter cycle changes. DTI was used to measure peak systolic flow velocity (VS), peak early diastolic flow velocity (VE), and peak late diastolic flow velocity (VA) of the middle and basal segments of the anterior wall of left ventricle. Finally, animals were sacrificed by anesthesia, and myocardial infarction region was stained with 5-Brdu immunohistochemical staining, and anti-TnT staining. RESULTS: Twelve rabbits were excluded because of death after operation.① Echocardiography: Imaging of 36 rabbits were clear in 1 day before myocardial infarction, 2 weeks after myocardial infarction, and 4 weeks after implantation. The sizes and systolic function of LV in 36 rabbits were normal before operation. Two weeks after operation, the sizes of LV became larger, the anterior wall of LV became thinner, and systolic range became weaker even disappeared. EF, CVIB, Vs, and Ve were lower (P < 0.05) and All was higher in both groups than pre-operation (P < 0.05). Four weeks after implantation, compared with control group, left ventricular diastolic diameter (LVDd) was smaller and systolic range became larger, All descended. EF, Vs, Ve and CVIB increased (P < 0.05).② Myocardial immunohistochemical detection: Numerous of Brdu-labeled positive cells were scattered, and anti-TnT was positive, which clearly showed horizontal stria of myocardium. However, normal myocardium was negative. CONCLUSION: Bone marrow MSCs after implantation can survive in ischemic myocardium and improve cardiac function. IBS and DTI can real-timely and exactly detect functional changes of infarction myocardium after bone marrow MSCs implantation.