Objective To evaluate the myocardial protective effect of hyperpolarized heart arrest at different temperature during cardiopulmonary bypass CPB.Methods Eighteen dogs were randomly allocated to be infused with St.Thomas solution containing 50?mol/L pinacidil and 5mmol/L K + at 37℃ (group A) or 4℃ (group B), or the standard St.Thomas solution containing K + 16mmol/L at 4℃ (group C) respectively, through aortic root after aortic clamping . The global surgical ischemia lasted 60min with the declamping of 20min .The activities of serum myocardial enzymes, and levels of lipid peroxide and adenine nucleotide of myocardium were measured.Results All paramaters showed to occur serious ischemic and reperfusion damages during the whole procedures in group C, while there were the mild damages in two hyperpolarized groups, especially in group B.Conclusions Myocardial protective effect of hyperpolarized arrest induced with pinacidil, an ATP sensitive potassium channel opener, is superior to that of traditional hyperkalemic cardioplegia , which is much more prominent in hypothermic state.

Objective To evaluate the myocardial protective effect of hyperpolarized arrest induced with ATP-sensitive potassium channel opener ,pinacidil in vitroMethods Twenty-four rabbit hearts were randomly divided into three groups : hypothermic hyperpolarized group (LH group), normothermic hyperpolarized group ( WH group), and hyperkalemic control group (group C) The isolated rabbit hearts with a Langendorff apparatus were perfused oxygenated Krebs-Henseleit's solution (K-H) for 10 min and followed by cardioplegia The cardioplegia consisted of StThomas solution with either traditional high potassium (16mmol/L KCl, 4 ℃, group C), or pinacidil 50?mol/L (4 ℃ in LH group or 37 ℃ in WH group ) with 5mmol/L KCl The hearts were subjected to 40 min perfusional occlusion and followed by 20 min reperfusionResults Hearts were arrested quickly in LH group, and a little slowly in WH group, but rebeated quickly , which were different significantly from those in group C ; Recovery of LVP and left ventricle contracility in LH group and WH group were remarkedly faster than those in group C (P

Objective To compare the myocardial protective effect of hyperpolarized cardioplegic arrest with pinacidil against that of depolarized hyperkalemic arrest during cardiopulmonary bypass Methods Eighteen healthy mongrel dogs of both sexes weighing 10 15kg were divided into three groups of six each, according to the cardioplegic solution infused into aortic root after aortic cross clamp was applied; group A received 4℃ standard St Thomas solution (K +16mmol/L); group B 37℃ St Thomas solution (K +5mmol/L) containing pinacidil (50?mol/L) mixed with blood (the ratio was 1:1);group C 4℃St Thomas solution (K + 5mmol/L) containing pinacidil(50?mol/L) mixed with blood (1∶1) The global ischemic time was 60min followed by 30min reperfusion Myocardial tissue was taken before and 30min, 60min after aortic cross clamping and 30min after reperfusion for determination of myocardial content of adenine nucleotide and MDA and ultrastructure examination with electron microscope Hemodynamics (BP,CVP,PCWP,CO,CI and LVSW) was also measured before aortic cross clamping and 15,30min after declamping Results Significant ischemic and reperfusion damages were found in group A, while there were only mild damages in group B and C Hemodynamics recovery after aortic declamping was significantly better in group C than that in group A and B Conclusions Myocardial protective effect of hyperpolarized arrest produced by blood cardioplegic solution containing pinacidil is superior to that of traditional depolarized hyperkalemic arrest and hypothermic hyperpolarized cardioplegia is better than normothermic

Objective To compare the myocardial protective effect of pinacidil-induced hyperpolarized and hyperkalemic depolarized cardiac arrest on isolated rabbit heart under different temperature. Methods Forty-eight rabbits of both sexes weighing 2.0-2.5 kg were sacrificed by a knock on the head. Their hearts were excised and perfused in a Langendorff apparatus with an oxygenated Krebs-Hensleit buffer (KHB)(37℃). The study was divided into six groups: A normothermic hyperkalemic cardioplegia; B normothermic hyperkalemic blood cardioplegia; C hypothermic hyperkalemic cardioplegia; D hypothermia hyperkalemic blood cardioplegia; E normothermic hyperpolarizing blood cardioplegia; F hypothermic hyperpolarizing blood cardioplegia. Three pieces of myocardial tissue were obtained from apex of left ventricle at the end of the study for determination of myocardial adenine nucleotide and lipid peroxide content and microscopic examination. The following were recorded : (1) cardiac arrest time: the time from perfusion with cardioplegic solution to the beginning of cardiac arrest. (2) heart beat recovery time ;the time from reperfusion with KHB to the beginning of normal heart beat. (3) changes in HR, left ventricle developed pressure and myocardial contractility before and after cardiac arrest. Results The cardiac arrest time was longer and the time for the heart to restart was shorter in the two hyperpolarizing blood cardioplegia groups (group E and F) than that in the other 4 groups. No arrhythmia occurred in group E and F. Left ventricle developed pressure(LVDP) and left ventricle contractility recovered quickly after reperfusion with KHB was started and were restored to the pre-ischemia level after 20 min in group E and F. The levels of ATP, TAN and EC were higher and the MDA level was lower in group E and F than those in the other 4 groups. Myocardial structure was less injuried in group E and F. Conclusion The myocardial protection effect of hyperpolarizing blood cardioplegia with pinacidil is superior to traditional hyperkalemic depolarizing cardioplegia.

Objective To investigate the effect of ischemic preconditioning ( IP) on the content of myocardial mitochondria cardiolipin and the heart function in isolated rat hearts. Methods Seventy-two healthy SD rats of both sexes ( 36 males,36 females) weighing 200 to 300 g were randomly divided into 4 groups ( n =18 for each group) : normal group,control group,IP group ( IP) and 5-hydroxydecanoate ( 5-HD) plus IP group ( HD) . Langendorff apparatus were used to establish the model of ischemia/reperfusion in isolated rat hearts. The hearts were perfused for 20 min to get stabilization followed by continuous perfusion in normal group for 100 min. In control group,after perfusing of 20 min for stabilization followed by continuous perfusion for 30 min,the hearts were then reperfused for 30 min after 40 min ischemia. In IP group,the hearts were given a 5-minute ischemia and 5-minute reperfusion for twice in order within a brief intermittent period,and ischemia reperfusion was carried out in the same way as that in control group. In HD group,the hearts were perfused with 100 ?mol/L 5-HD before IP,and the following procedures were carried out as those in IP group. HR,left ventricular end-diastolic pressure ( LVEDP) ,left ventricular developed pressure ( LVDP) were recorded at the end of stable perfusion ( T1) ,immediately before ischemia ( T2) and at the end of reperfusion ( T3) in all the groups. The content of myocardial mitochondria cardiolipin was measured with HPLC. Results When theparameters at T3 were compared with those at T1 and T2,HR and LVDP were decreased,LVEDP was increased and the content of myocardial mitochondria cardiolipin was decreased. All these changes were significant ( P

The myocardial protective effect of continuous infusion with normothermic oxygenated crystalloid solution or blood cardioplegia during normothermic CPB was studied in 15 dogs. Ultrastructure. levels of adenine nucleotides,lipid peroxide (LPO),water content of heart musle,hemodynamics were observed. Dogs were randomly divided into three groups. Group Ⅰ: intermittent infusion with cold crystsalloid cardioplegia during hypothermic CPB (n=5); Group Ⅱ: continuous infusion with normothermic oxygenated blood cardioplegia during normothermic CPB(n=5); Group Ⅲ: continuous infusion with normothermic oxygenatde crystalloid cardioplegia duriug normothermic CPB((n=5). The normal mitochandria contents and glycogen stores in group Ⅱ and Ⅲ were significantly higher than those in group Ⅰ(P

ve To assess the protective effect of L-arginine on vascular endothelial cell during cardiopulmonary bypass(CPB). Methods 12 adult healthy mongrel dogs of either sex weighing 10-15kg, were divided into L-arginine group (group L, n=6) and control group (group C, n=6) . Femoral artery and vein were cannulated for monitoring of MAP and CVP. Right internal jugular vein was cannulated with Swan-Ganz catheter for hemodynamic monitoring. L-arginine 100 mg?kg-1 was administered intravenously before CPB followed by continuous intravenous infusion at 10mg?kg-1.min-1 to the end of CPB in group L. Control group was treated as group L except the administration of L-arginine. Venous blood samples were taken before CPB, 5min after CPB was started, 15, 45min after aortic cross-clamping and 15, 30min after release of aortic cross-clamp for determination of the plasma levels of metabolites of nitric oxide (NO2- and NO3-), malondialdehyde (MDA) and von Willebrand Factor(vWF). Hemodynamic parameters were measured before CPB, 15 and 30min after release of aortic clamp. Specimens of tissue from femoral artery and descending aorta were taken for microscopic examination at 15,45 min after aortic cross-clamping and 30min after release of aortic cross-clamp.Results There was little difference in plasma NO2- and NO3-concentrations before CPB between the two groups. NO2- and NO3- levels increased significantly after CPB in both groups but were significantly higher in group L than those in group C (P

Purpose Progressive hypertensive intracerebral hemorrhage (PHICH) is often observed in clinical ward,but its prognosis is undetermined.This study is to investigate the duration and the risk factors of progressive hypertensive intracerebral hemorrhage.Methods The diagnosis of PHICH was determined by comparing the first and second CT scans.Potential risk factors including the sex,age,location of hematoma,blood pressure,coagulopathy and the duration of admission to the first CT scan were analyzed.Results In a cohort 143 patients,the PHICH were found in 41 cases(28.7%)after the second scan,and among them,32 patients(22.4%)were necessary to perform craniotomy for evacuation of hematoma,most of the PHICH occurred within 24 hours after onset.Older age,thalamus bleeding,high systolic blood pressure within 6 hours,coagulapathy and shorter duration from admission to the first CT scan were the predictors associated with PHICH.Conclusion PHICH occurs in almost 1/4 of hypertensive intracerebral hemorrhage,predominantly in elder,thalamus bleeding,coagulapathy,high systolic blood pressure within 6 hours and shorter duration between onset and the first CT scan.CT examination within 24 hours after admission is crucial to reveal the exact condition of the patient.

Objective To investigate the expression of osteopontin(OPN) mRNA and its correlation with clinicopathologic features of glioma. Methods The expression of OPN mRNA was detected by semi-quantitive RT-PCR in 60 cases of gliomas and their correspondent normal tissues.The relationship between the relative content of OPN mRNA and clinicopathologic features of glioma was also analyzed. Results The positive rate of OPN mRNA expression was 73.3%(44/60) in our group.The OPN mRNA expression in normal brain tissue was all negative.Furthermore,the OPN mRNA expression was associated with the pathological grade of glioma.All patients were followed up for an average of 12 months.We did observed that the OPN mRNA expression positive group(44 cases) had recurrence in 36 patients and the negative group(16 cases) had only 2 case with recurrence (P

Objective: To study the protective effect of coenzyme Q_10 on red blood cell membrane and its immunity in patient during extracorporeal circulation. Method: Twenty patients under extracorporeal circulation about 30 minutes were randomly divided into control group and coenzyme Q_10 group (n=10). Coenzyme Q_10 2mg/kg was added to the priming fluid in coenzyme Q_10 group. Plasma levels of malondialdehyde (MDA), free hemoglobin (FHb), immune adhe sion ability and immune compound of red blood cell membrane were measured before extracorporeal circulation, 15 and 30 minutes after beginning of cardiopulmonary bypass, and on first day morning after operation. Result; All different periods after beginning of cardiopulmonary bypass in coenzyme Q_10, group, MDA and FHb levels were lower and im mune adhesion ability was higher than those of control group. Conclusion: Coenzyme Q_10 may protect red blood cell membrane and its immunity of patient during extracorporeal circulation.