Objective　To study β-AR density relativity between porcine myocardial tissue and circulating lymphocytes and clinical significance ．Methods　 48 porcines(seven months old），were　taken a few of myocardial tissue and peripheral blood．Assay　β-AR density with radioactive isotope to study the　relativity．Results　Scatter plot of β-AR　density　 circulating lymphocytes and myocardial tissue showed　 linear　Correlation（r＝0.845，P＜0.001　Y＝0.002527X＋0.726）．Conclusion　There　was　obvious　 correlation on β-AR　density in circulating lymphocytes and myocardial membrane　of pigs．Determination of β-AR　density　in　circulating lymphocytes can reflect alteration of that in myocardial tissue．Therefore，we can use it to monitor and investigate　self-induced and drug-induced β-AR changes．

Objective To investigate the effect of heme oxygenase-1 (HO-1) on hypoxia-reoxygenation (H/R) injury in cultured neonatal rat cardiomyocytes. Methods Primary cultured neonatal rat cardiomyocytes were randomly divided into4 groups: Ⅰ control group (group C), Ⅱ H/R group, Ⅲ hemin group and Ⅳ hemin+zinc protoporphyrin (ZnPP) group. In group H/R, the cardiomyocytes were exposed to 2 h of hypoxia followed by 6 h of reoxygenation. Hemin was added to the culture medium with a final concentration of 20 μmol/L 24 h before hypoxia and immediately before hypoxia in group hemin. Hemin and ZnPP were added to the culture medium with final concentrations of 20 μmol/L 24 h before hypoxia and immediately before hypoxia in group Henin + ZnPP. The cells were incubated in 35 mm culture dishes (2 ml in each dish) and 50 ml culture flasks (3 ml in each flask)(45 dishes and 3 flasks in each group). The HO-1 expression, cell survival rate, LDH activity, malondialdehyde (MDA) level and superoxide dismutase (SOD) activity were detected after the end of reoxygenation. Results Compared with group C, the LDH activity, MDA level and HO-1 expression were significantly increased, while the cell survival rate and SOD activity decreased in the other three groups ( P ＜ 0.05). Compared with group H/R,the LDH activity and MDA level were significantly decreased, while the HO-1 expression, cell survival rate and SOD activity increased in group hemin ( P ＜ 0.05 ), but no significant change was found in group hemin + ZnPP (P ＞0.05). H/R injury was obvious in group H/R and hemin + ZnPP, but was significantly attenuated in group hemin. Conclusion HO-1 can protect cardiomyocytes against H/R injury in neonatal rats.

Objective To study the expression of EI-1 in myocardium during cerebral ischemia and reper-fusion, and to investigate the mechanism of cerebral cardiac syndrome. Method Two hundred and eight SD rats weighting 220～250 gram, were divided into three groups: sham control group (n=48), cerebral ischemia group (n=80), cerebral ischemia/reperfusion group (n=80). The area of cerebral ischemia, and the concentration of sennn ET-1 and CK-MB, and the content of myocardial ET-1 were determined in 0,6, 12,24,48,72 h after cerebral ischemia and reperfusion, and were analyzed by t-test or F-test. Results Cerebral necrosis area was ob-served at 6 h after cerebral ischemia in cerebral ischemia group, and peaked at 12 h (P>0.05). The concentra-tion of CK-MB increased gradually after cerebral ischmia, peaked at 12 h (P<0.05), and then gradually de-creased. The serum concentration of ET-1 peaked at 6 h and then gradually decreased. The content of ET-1 in my-ocardium began to increase at 6 h after cerebral ischemia, and peaked at 12 h (P<0.05). In cerebral ischemia/reperfusion group, all of cerebral necrosis size, CK-MB concentration and myocardial ET-1 concent paelced at 12 h and then gradually decreased (P<0.05). Change of ET-1 concentration in blood was similar to that in cerebral ischemia group. Compared with cerebral ischemia group, the size of cerebral necrosis reduced obviously at 24 h,48 h,72 h in cerebral ischemia/reperfusion group (P<0.05). The concentration of CK-MB in cerebral ischemia/ reperfusion group was higher than that in cerebral isehemia group (P<0.05). The peak time of myocardial ET-1 was shatened in cerebral ischemia/reperfusion group. The change of serum ET-1 was not different between two groups. Conclusions Large area of cerebral ischemia, might cause myocardial injury. ET-1 is involved in the course of myocardial injury following cerebral ischemia. Though cerebral reperfusion can protect brain,but it make myocardial injury more serious,and ET-1 might participate in this course.

Objective To study the cardioprotection effects of heme oxygenase-1(HO-1)on cardiopulmonary resuscitation(CPR).Method Male Sprague-Dawley rats were asphyxiated for 9 minutes and resuscitated.Rats wefe randomly divided into 4 groups,namely,sham asphysiation group,CPR group,Hemin group and Heroin +ZnPP group(zinc protoporyphyrin IX).Resuscitated groups were further divided into two subgroups according to various intervals:6 hours and 24 hours after resuscitation.Hemodynamic was observed.Serum creatine phosphokinase-MB(CPK-MB)and lactate dehydrogenase were determined.HO-1 in heart tissue homogenates was assayed.Ultrastructure of rats hearts was examined.Statical evaluation was performed with analysis of variance.Results The mean blood pressure(MBP)in resuscitated groups was significantly reduced after resuscitation,hadn't any difference between supgroups.The scores of dp/dt 40 and-dp/dt were significantly decreased in CPR group and Hemin+ZnPP group after resuscitation(all P＜0.05),but dP/dt40 in Heroin group did nol differ significantly after resuscitation.and-dp/dt decreased only 0.5 hours and one hour after resuscitation and returned to baseline values two hours after resuscitation.The scores of dp/dt 40and-dp/dt in Heroin group at different intervals after resuscitation were significantly higher than those in CPR group and Hemin+ZnPP group(all P＜0.05).Serum CPK-MB and LDH in CPR group and Hemin+ZnPP group at 6 hours and 24 hours after resuscitation were significantly higher than those in Hemin group(all P＜0.05).The cardiac tissue ultrastructure of rats in Hemin group was more intact than that of CPB group and Hemin+ZnPP goup.HO-1 levels in heart tissue homogenates of Hemin group at 6 hours and 24 hours after resuscitation were significantly higher than those in CPR group and Heroin+ZnPP group(all P＜0.05).Conclusions HO-1 expression induced by Heroin can effectively improve post-resuscitation myocardial dysfunction,alleviate cardiac injury,keep the ultrassructure integrity of cardiac myocytes.It may be a new approach to treat myocardial dysfunction after resuscitation.

Objective To investigate the effects of mitochondrial division inhibitor 1 (mdivi-1) in rats after cardiopulmonary resuscitation (CPR) and its mechanism.Methods Fifty Sprague-Dawley (SD) rats were randomly (random number table) divided into sham group (n =8),cardiac arrest (CA) model group (n =14),dimethyl sulfoxide post-treatment control group (DMSO group,n =14),and mdivi-1 post-treatment group (mdivi-1 group,n =14).Asphyxial CA was reproduced in animals,and they were resuscitated by CPR.In the mdivi-1 group or DMSO group,the animals were given mdivi-1 (1.2 mg/kg) or DMSO (0.1％) intravenously after restoration of spontaneous circulation (ROSC).The neurological functions were assessed using neurological deficit score (NDS) determined at 24,48 and 72 hours after CPR.The brain tissues were harvested at 72 hours after CPR.The histopathologic changes were assessed by hematoxylin and eosin (HE) staining,and the normal neuron was counted.The neuronal apoptosis was assessed with terminal dexynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) staining,and the expressions of cytochrome C (Cyt-C) protein in mitochondria and cytoplasm from hippocampus were determined by Western Blot.Results NDS in all experiment groups was gradually increased after CPR,and they were significantly lower than thoseo.f the sham group at 24,48,and 72 hours (51.5±3.7 vs.80.0±0.0,59.3±3.6 vs.80.0±0.0,66.7±2.6 vs.80.0±0.0,all P ＜ 0.05).The number of normal pyramidal neurons in the hippocampal CA1 region was markedly reduced (cells/HP:4.4± 1.1 vs.23.1 ± 4.0,P ＜ 0,05),the apoptotic index was significantly increased [(86.9 ± 6.9)％ vs.(3.4 ± 0.8)％,P ＜ 0.05],the expressions of Cyt-C in mitochondria were significantly decreased (A value:0.46±0.18 vs.1.00±0.00,P ＜ 0.05),and the expressions of Cyt-C in cytoplasm were significantly up-regulated (A value:6.65±0.21 vs.1.00±0.00,P ＜ 0.05).Compared with the CA group,NDS at 24 hours and 48 hours in mdivi-1 group was slightly increased (55.2 ± 3.3 vs.51.5 ± 3.7,64.7 ± 2.4 vs.59.3 ± 3.6,both P ＞ 0.05),and it was significantly increased at 72 hours (74.5±2.3 vs.66.7 ± 2.6,P ＜ 0.05),the number of normal pyramidal neurons in the hippocampal CA1 region was markedly increased (cells/HP:16.2±2.4 vs.4.4± 1.1,P ＜ 0.05),the apoptotic index was dramatically reduced [(42.3 ± 3.9)％ vs.(86.9 ± 6.9)％,P ＜ 0.05],the expressions of Cyt-C in mitochondria were significantly increased (A value:0.83 ± 0.22 vs.0.46 ± 0.18,P ＜ 0.05),and the expressions of Cyt-C in cytoplasm were significantly decreased (A value:3.84±0.47 vs.6.65±0.21,P ＜ 0.05).There was no statistically significant difference in above indexes between CA group and DMSO group.Conclusion By inhibiting mitochondrial Cyt-C apoptotic pathway to reduce neuronal apoptosis in rats after CA-CPR,mdivi-1 can improve brain function after CPR.

Objective To investigate the resuscitation outcome after a short period of mild hypothermia in porcine model of prolonged ventricular fibrillation (VF).Methods Fourteen male healthy domestic swine weighting 34 to 36 kg were used.VF was induced electrically and maintained untreated for 11 mins,followed by manual cardiopulmonary resuscitation (CPR) procedure.Two investigators initiated chest compression and bag-valve mask ventilation in pattern of 2 min rotation.A biphasic wave of 120 J electric defibrillation (ED) was attempted 6 mins after CPR.If there was no return of spontaneous circulation (ROSC),CPR was restored and ED was delivered when necessarily.Resuscitation was considered unsuccessful if absence of ROSC for 12 mins.However,if ROSC occurred,animals were randomly (random number) diveded into normothermia (NT) group and hypothermia treatment (CH) group.Animals in CH group were immediately cooled by using intravenous infusion of ice-cold saline and surface cooling.Core temperature was reduced to 32-34 degrees centigrade within 120 mins and maintained at this level for 2 h.Active rewarming was completed within 2 h until baseline body temperature was reached.Data of hemodynamic variables,blood-gas analysis and blood lactate before VF of two groups were recorded.Meawhile,cardiac output (CO),heart rate and Tc after ROSC were recorded.Neurological defect scores (NDS) were evaluated every 24 h until 96 h after ROSC.Variables were compared using either Fisher test or repeated measures analysis of variance,followed by Bonferroni for multiple comparisons.A two-sided P value ＜0.05 was regarded statistically significant.Results There was no significant difference in body weight,mean arterial pressure,CO,pH,pressure of end-tidal carbon dioxide (ETCO2) and lactate between groups before VF.In the period of CPR,there were also no significant difference in total resuscitation time,first shock success rate,ROSC rate,shock ROSC rate,total number of shock and doses of epinephrine.However,animals in CH group survived longer time than that in NT groups [(96.00 ± 0.00) hvs.(49.71 ±43.65) h,P=0.031].Meanwhile,the survival rate of 96 h was significantly higher in CH than that in NT (P ＜ 0.05).For neurological function,there was a obviously better NDS in CH group than that in NT group within ROSC 96 h (P ＜ 0.05).Conclusion Even a short duration of 2 hour mild hypothermia could improve resuscitation outcome in porcine model of 11 minute VF.

Objective To explore the therapeutic potential and mechanism of stem cells mobilized by granulocyte colony-stimulating factor (G-CSF) and AMD3100 to repair global cerebral ischemia injuries in a rat model of cardiac arrest (CA) and cardiopulmonary resuscitation (CPR).Methods Cardiac arrest was induced by asphyxia.Fifty-six SD rats were randomly assigned into four groups:G-CSF group,G-CSF + AMD3100 group,CPR control group and sham operated group.The animals were sacrificed at 3d and 6d after CPR respectively.The neurological status and morphological changes of damaged cerebrum,the apoptosis of nerve cells and vascular endothelial growth factor (VEGF) expressed in brain tissue and capillary density in hippocampus and temporal lobe cortex were measured and analyzed by means of neurological deficit score (NDS),adhesive tape removal test (TRT),ELISA,MRI and immunofluorescence.Results NDS in G-CSF + AMD3100 group (61.4 ± 10.7) was significantly higher than that in CPR control group (49.9 ± 10.4) at 3 d after CPR (P ＜0.05).And less time consumption for TRT found in G-CSF + AMD3100 group (85.5 ±28.9) s rather than was in CPR control group (148.1 ± 23.8) s and G-CSF group (118.5 ± 30.4) s (P ＜ 0.05).The severity of cerebral injury assessed by MRI was significantly milder at both 3 d and 6 d in the two stem cell mobilization groups.The apoptosis rate of nerve cells in G-CSF + AMD3100 group (0.23 ± 0.06) was significantly lower than that in G-CSF group (0.34 ±0.08) at 3 d after CPR,and that in both stem cell mobilization groups was lower than that in CPR control group (0.44 ± 0.09) (P ＜ 0.05).At 3 d and 6 d after CPR,the levels of VEGF in brain tissue were (106.2 ±23.3) pg/mL and (79.9 ± 18.4) pg/mL in G-CSF + AMD3100 group,and were (50.6 ± 13.7) pg/mL and (73.9 ± 16.6) pg/mL in G-CSF group,which were both significantly higher than that in CPR control group (23.1 ± 10.2) pg/mL and (36.2 ± 12.8) pg/mL (P ＜0.05).At 3 d after CPR,the cerebral capillary density (351.8 ±67.9) branches in every high power field (A/HPF) was significantly higher in G-CSF + AMD3100 group than that (301.4 ± 77.3) A/HPF in G-CSF group and (250.4 ± 48.0) A/HPF in CPR control group (P ＜ 0.05).The cerebral capillary density in G-CSF group elevated to (348.4 ±76.7) A/HPF at 6 d after CPR which was significantly higher than that at 3 d (P ＜0.05),and there was no difference between that at 3 d and 6 d in G-CSF + AMD3100 group.Conclusions The mobilization stem cells improve the impaired neurological function.The increased expression of VEGF in brain tissue,the neo-vascularization promoted by the mobilized stem cells and the inhibition of nerve cell apoptosis may be associated with the protective effects of the stem cell mobilization.

Objective To compare the difference in cardiac injuries between asphyxia and ventricular fibrillation modes in different periods after cardiac arrest (CA).Methods The model was established in Cardiopulmonary Resuscitation Lab,Sun Yat-sen University.A total of 35 male SD rats were used to produce the asphyxia or ventricular fibrillation (VF) cardiac arrest models randomly.Both of the two modes were induced 8 minutes cardiac arrest.The myocardial HE stains,mitochondrial respiratory control ratio (RCR),and echocardiography were observed at 4 h,24 h and 72 h after ROSC (restoration of spontaneous circulation).The results were expressed as (-x ± s),t test was performed to compare between two groups,and one way analysis of variance was used to compare multiple groups.P ＜ 0.05 was considered as significant difference.Results HE stains showed damages were more serious in the VF mode than in asphyxia mode at 4 h,and both of them had a disorderly-arranged myocardium at 72 h.RCR in VF mode became worse at 4 h,and RCR resumed at 24 h in both modes without significant difference compared with the sham operated rats.The echocardiography showed VF mode had a lower left ventricular ejection fraction (LVEF) than asphyxia mode at 4 h (29.68％ vs.42.16％,P =0.03),and there was no difference in LVEF between VF mode and the sham operated rats at 24 h,however no difference in LVEF between the asphyxia and sham operated rats at 72 h.Both of them had a thicker left ventricular anterior wall than the sham operated rats at 72 h (2.41 mm vs.1.72 mm,P=0.013; 2.61 mmvs.1.72 mm,P=0.007),and there was no significant difference between them.Conclusions The ventricular fibrillation mode has a more severe injuries in early period,but it recovers sooner than asphyxia one.Both of two groups get compensatory left ventricular hypertrophy in later period of ROSC.

Objective To investigate the protective role of carbon monoxide releasing molecule-2 (CORM-2) in post-resuscitation myocardial dysfunction (PRMD) in rat models of cardiopulmonary resuscitation (CPR).Methods Cardiopulmonary resuscitation model was established after cardiac arrest induced by ventricular fibrillation.Male healthy Sprague-Dawley (SD) rats were randomly (random number) divided into 4 groups according to random number table:control group,CORM-2 group,inactive CORM-2 (iCORM-2) group and Sham group,in which the equal volume (1 mL) of 0.2％ DMSO,50 μmol/kg CORM-2,50 μmol/kg iCORM-2 and 0.2％ DMSO were respectively administered into the rats of these groups after resuscitation.The ejection fraction (EF) of left ventricle and myocardial performance index (MPI) were measured to detect the myocardial function by echocardiography at 12 hours after resuscitation.Mitochondrial respiration was assessed with Clark oxygen electrode at the same time.Western blot was used to determine the ratio of mitochondrial cytochrome c (cyt c) to cytoplasmic cyt c as well as caspase-3 level.Multiple comparisons were made by analysis of variance.Results Compared with the control group,higher EF and MPI,higher state Ⅲ respiration rate and respiratory control rate (RCR) of mitochondria,and decreased ratio of mitochondrial cytc/cytoplasmic cyt c and lower caspase-3 level were observed in the CORM-2 group (P ＜ 0.05).However,there were no significant differences in above biomarkers found between iCORM-2 group and control group (P ＞ 0.05).Conclusions The CO released from CORM-2 might improve mitochondrial respiration and PRMD by inhibition of myocardial apoptosis via a mitochondrial pathway.

Objective To study the protective effect of δ-opioid receptor agonist DADLE Oil hypoxia-in-duced injury of rat cortical neuronfl.Method Cortical neuron,q cultured for 8,lays were assessed by MAP2 im-munofluorescenee and randonly divided into hypoxia group(n=6),and DADLE preconditioning plus hypoxia group(n=6),normoxia group(n=6),and DADLE preconditioning plus normoxia group(n=6).The cells in hyoo O'oup Were cultured in a hyooxic incubator containing I%02,5%c02,and 94%N2 at 37℃.The cens in DADLE preconditioning groups Wel'preconditioned with 10 ttmol/L DADLE before culture.The cells in normoxia group were cultured in an incubator COntaining95%air and 5%c02 at 37℃.The survival rate ofneu.rOllS cultured for 72 hours was analyzed with hochest-33258 staining,and lactate dehydrogenase(LDH)release Wills detected.Glucose in the culture medium was detected to assess glucose/energy metabolism.The data of LDH re.1ease and ducose level were analyzed by A.NOVA.and cell survival rates wG:qanalyzed by Chi-square Tests.Re.vtats When cortical neurons were cultured for 8 davs,95%the cells were cortical neurous as assayed by MAP2 immunofluorescence·Cell survival rate was significantly higher in DADLE preconditioning Cus hypoxia group than in hypoxia group[(71.88±1.77)%vs.(43.58±3.07)%(P<0.05)].LDH release was significantly lower in DADLE preconditioning plus hypoxh group than in hypoxgroup[(3824.27±294.86)vs.(4516.59±605.02),P<0.05].Glucose level in the culture medium was significantly higher in DADLE preconditioning plus hypoxia group than in hypoxia group[(11.92-4-2.05)mmol/L vs.(9.88±0.71)mmol/L,P<0.051.Conclusions 6-opioid receptor agonist DADLE Can protect rat cortical neurons from hypoxia injury, which might be the mechanism of reducing glucose/energy metabolism in cortical neurons during the period of hypoxia.