Frequency and Voltage-dependent Inhibition of Delayed Outward Potassium Current by Flecainide in Isolated Atrial Cell of Guinea Pig Heart

Effects of flecanide on membrane currents were studied using an isolated single atrial cell from guinea pig hearts. The tightseal cell clamp technique was used. In the current clamp condition, flecainide prol(?)nged significantly the atrial action potential (APD) with frequency dependence.Delayed outward K current (I_k) and outward tail current were specifically inhibited by flecainide in a frequency and concentration fashion. Flecainide inhibit(?)d I_k more strongly as the membrane potential become more positive from+10mV to+60mV.The value of I_k was attenuated to 0.973 nA from 1.105 nA of control and the value of tail current was reduced to 0.113 nA from 0.288 nA of control at 60 mV. The drug did not affect on the holding current.The effects of flecainide on the action potential and transmembrane ionic currents strongly suggest that the main mechanism of action of this agent is to inhibit Voltage-dependent potassium current. In the Voltage clamp condition, flecainide affected neither the conventional L type Ca~(2+) current nor the I~(k1) current significantly. Our research proved that F1e was not completely consistent with class Ic agents, because F1e could markedly increase the APD in the experiment.     

High extracellular potassium ion concentration attenuates the blockade action of ketanserin on Kv1.3 channels expressed in xenopus oocytes

Background Ketanserin （KT）, a selective serotonin （5-HT） 2-receptor antagonist, reduces peripheral blood pressure by blocking the activation of peripheral 5-HT receptors. In this study electrophysiological method was used to investigate the effect of KT and potassium ion on Kv1.3 potassium channels and explore the role of blocker KT in the alteration of channel kinetics contributing to the potassium ion imbalances. Methods Kv1.3 channels were expressed in xenopus oocytes, and currents were measured using the two-microelectrode voltage-clamp technique. Results KCI made a left shift of activation and an inactivation curve of Kv1.3 current and accelerated the activation and inactivation time constant. High extracellular [K^＋] attenuated the blockade effect of KT on Kv1.3 channels. In the presence of KT and KCI the activation and inactivation time constants were not influenced significantly no matter what was administered first. KT did not significantly inhibit Kv1.3 current induced by tetraethylammonium （TEA）. Conclusions KT is a weak blocker of Kv1.3 channels at different concentrations of extracellular potassium and binds to the intracellular side of the channel pore. The inhibitor KT of ion channels is not fully effective in clinical use because of high [K^＋]. and other electrolyte disorders.     

Effects of Xinjining(心悸宁) Extract on Inward Rectifier Potassium Current in Ventricular Myocytes of Guinea Pig

<正>Objective:To study the effect of Xinjining extract(心悸宁,XJN) on inward rectifier potassium current(I_(K1)) in ventricular myocyte(VMC) of guinea pigs and its anti-arrhythmic mechanism on ion channel level. Methods:Single VMC was enzymatically isolated by zymolisis,and whole-cell patch clamp recording technique was used to record the I_(K1) in VMC irrigated with XJN of different concentrations(1.25,2.50,5.00 g/L;six samples for each).The stable current and conductance of the inward component of I_(K1) as well as the outward component of peak I_(K1) and conductance of it accordingly was recorded when the test voltage was set on -110 mV.Results:The suppressive rate of XJN on the inward component of I_(K1) was 9.54%±5.81%,34.82%±15.03%,and 59.52%±25.58%with a concentration of 1.25,2.50,and 5.00 g/L,respectively,and that for the outward component of peak I_(K1) was 23.94%±7.45%,52.98%±19.62%,and 71.42%±23.01%,respectively(all P0.05).Moreover, different concentrations of XJN also showed effects for reducing I_(K1) conductance.Conclusion:XJN has inhibitory effect on I_(K1) in guinea pig's VMC,and that of the same concentration shows stronger inhibition on outward component than on inward component,which may be one of the mechanisms of its anti-arrhythmic effect.     

Overexpression of connexin 45 in rat mesenchymal stem cells improves the function as cardiac biological pacemakers

Background Extensive research toward creating a biological pacemaker by enhancement of inward depolarizing current has been performed. However, studies have mainly focused on inducing spontaneous activity and have not adequately addressed ways to improve pacemaker function. In this study we attempted to improve pacemaker function by altering connexin expression in rat mesenchymal stem cells （MSCs） to a phenotype similar to native sinus node pacemaker cells. Methods To generate a biological pacemaker, MSCs were transduced with a cardiac pacemaker gene- hyperpolarization-activated cyclic nucleotide-gated channel 4 （HCN4）, via transfection with a lentiviral vector. Funny current （If） in HCN4~ MSCs was recorded by voltage-clamp. Overexpression of connexin 45 （gene Gja7） in MSCs was achieved by transfection with the plasmid pDsRED2-N1-Gja7-RFP. Double-immunolabelling with anti-connexin 43 and anti-connexin 45 antibodies were used to identify the gap junction channels. The effects of the genetically modified MSCs on cardiomyocyte excitability were determined in MSCs cocultured with neonatal rat ventricular myocytes. Spontaneous action potentials of neonatal rat ventricular myocytes were recorded by current-clamp. Results High level time- and voltage-dependent inward hyperpolarization current that was sensitive to 4 mmol/L Cs＋ was detected in HCN4＋ MSCs, confirming that HCN4 acted as Ir channels in MSCs. Connexin 43 and connexin 45 were simultaneously detected in CX45＋ MSCs. Beating frequency was （82±8） beats per minute （n=-5） in myocytes cocultured with non-transfected control MSCs, versus （129±11） beats per minute （n=-5） in myocytes cocultured with HCN4＋ MSCs. Myocytes cocultured with MSCs cotransfected with HCN4 and connexin 45 had the highest beating frequency at （147±9） beats per minute （n=5）. Conclusion These findings demonstrate that overexpression of connexin 45 and subsequent formation of heteromeric connexin 45/connexin 43 gap junction channels in HCN4 expressing MSCs can improve their function as cardiac biological pacemakers in vitro.     

Size-dependent biological effects on vascular endothelial cells induced by different particulate matters

Summary： The contribution of particles to cardiovascular mortality and morbidity has been enlightened by epidemiologic and experimental studies. However, adverse biological effects of the particles with different sizes on cardiovascular cells have not been well recognized. In this study, sub-cultured human umbilical vein endothelial cells （HUVECs） were exposed to increasing concentrations of pure quartz particles （DQ） of three sizes （DQPM1, 〈1 μm; DQPM3-5, 3-5 μm; DQPM5, 5 μm） and carbon black particles of two sizes （CB0.1, 〈0.1 μm; CB 1, 〈 1 μm） for 24 h. Cytotoxicity was estimated by measuring the activity of lactate dehydrogenase （LDH） and cell viability. Nitric oxide （NO） generation and cyto- kines （TNF-α and IL-1β） releases were analyzed by using NO assay and enzyme-linked immunoabsorbent assay （ELISA）, respectively. It was found that both particles induced adverse biological effects on HUVECs in a dose-dependent manner. The size of particle directly influenced the biological activity. For quartz, the smaller particles induced stronger cytotoxicity and higher levels of cytokine responses than those particles of big size. For carbon black particles, CB0.1 was more capable of inducing adverse responses on HUVECs than CB 1 only at lower particle concentrations, in contrast to those at higher concentrations. Meanwhile, our data also revealed that quartz particles performed stronger cell damage and produced higher levels of TNF-α than carbon black particles, even if particles size was similar. In conclusion, particle size as well as particle composition should be both considered in assessing vascular endothelial cells injury and inflammation responses induced by particles.     

The electrophysiologic effects of endothelin. A patch clamp study in guinea pig ventricular myocytes.

To study the electrophysiologlc effects of endothelin-1 (ET-I), we used patch clamp and glass microelectrode techniques to investigate the effects of ET-1 on cardiac L-Ica, Ik and lk_2 in guinea pig ventricular myocytes. The prolongation of APD_50 was induced and EADs was triggered by 50 nM ET-I perfusion. L-Ica and Ik were enhanced by various ET-I concentration from I to 50 nM with dose-dependence. Their steady-state activations of L-Ica and Ik shifted left with ET-1 concentration increments. ET-1 elicited a kind of GTP- dependent inward rectifier K~ current having a mean conductance of 82.36± 1.27 pS. The open time and close time (both interburst intervals and burst durations ) abbreviated with ET-1 concentration increase. The results suggested that EADs-ET evoked was ascribed to the prolongation on the plateau level, which resulted from L-Ica inhancement. The ET- evoked inward rectifier K~ current should be further studied.     

EFFECT OF VASOPRESSIN ON DELAYED NEURONAL DAMAGE IN HIPPOCAMPUS FOLLOWING CEREBRAL ISCHEMIA AND REPERFUSION IN GERBILS

Mongolian gerbils were used as delayed neuronal damage (DND) animal models.At the end of 15 minute cerebral ischermia and at various reperfusion time ranging from 1 to 96 hours,the content of water and arginine vasopressin (AVP) in the CA1 sector of hippocampus were measured by the specific gravity method and radioimmunoassy.Furthermore,we also examined the effect of intracerebroventricular (ICV) injection of AVP,AVP antiserum on calcium,Na^ ,K^ -ATP ase activity in the CA1 sector after ischemia and 96 hour reperfusion.The results showed that AVP Contents of CA1 sector of hippocampus during 6 to 96 hour recirculation,and the water content of CA1 sector during 24 to 96 hour were significantly and continuously increased.After ICV injection of AVP,the water content and calcium in CA1 sector of hippocampus at cerebral ischemia and 96 hour recirculation further increased,and the Na^ ,K^ -AT-tion of AVP antiserum,the water contenr and calcium in CA1 sector were significantly decreased as compared with that of control.These suggested that AVP was involved in the pathopysiologic process of DND in hippocampus following cerbral ischemia and reprfusion.Its mechanism might be through the change of intracellular action mediated by specific AVP receptor to lead to Ca inos over-load of neuron and inhibit the Na^ ,K^ -ATPase activity,thereby to exacerbate the DND in hippocampus.     

Effect of etomidate on voltage-dependent potassium currents in rat isolated hippocampal pyramidal neurons

Background Previous studies demonstrated general anesthetics affect potassium ion channels, which may be one of the mechanisms of general anesthesia. Because the effect of etomidate on potassium channels in rat hippocampus which is involved in memory function has not been studied, we investigated the effects of etomidate on both delayed rectifier potassium current （IK（DR）） and transient outward potassium current （I_K（A）） in acutely dissociated rat hippocampal pyramidal neurons.Methods Single rat hippocampal pyramidal neurons from male Wistar rats of 7-10 days were acutely dissociated by enzymatic digestion and mechanical dispersion according to the methods of Kay and Wong with slight modification. Voltage-clamp recordings were performed in the whole-cell patch clamp configuration. Currents were recorded with a List EPC-10 amplifier and data were stored in a computer using Pulse 8.5. Student＇s paired two-tail t test was used for data analysis. Results At the concentration of 100 μmol/L, etomidate significantly inhibited IK（DR） by 49.2% at ＋40 mV when depolarized from -110 mV （P 〈0.01, n=8）, while did not affect IK（A） （/1=8, P 〉0.05）. The IC50value of etomidate for blocking IK（DR）was calculated as 5.4 μmol/L, with a Hill slope of 2.45. At the presence of 10 μmol/L etomidate, the V1/2 of activation curve was shifted from （17.3±1.5） mV to （10.7±9.9） mV （n=8, P 〈0.05）, the V1/2 of inactivation curve was shifted from （-18.3±2.2） mV to （-45.3±9.4） mV （n=8, P 〈0.05）. Etomidate 10 μmol/L shifted both the activation curve and inactivation curve of IK（DR））to negative potential, but mainly affected the inactivation kinetics.Conclusions Etomidate potently inhibited IK（DR） but not IK（A） in rat hippocampal pyramidal neurons. IK（DR） was inhibited by etomidate in a concentration-dependent manner, while IK（A） remained unaffected.     

EFFECT OF COXSACKIEVIRUS B3 ON ION CHANNEL CURRENTS IN RAT VENTRICULAR MYOCYTES

Objective. To investigate the effects of coxsackievirus B3 ( CVB3 ) on ion channel currents in rat ventricular my-ocytes. Methods. Rat hearts were isolated with collagenase to acquire single ventricular myocytes, L-type voltage-depen-dent calcium channel( VDCC) current (ICa),Na^ current (INa), outward potassium current (Iout), inwardly rectifying potassium current(IKI) were recorded using whole cell patch clamp techniques. Results. CVB3 infection increased Ica and Iout, while decreased IKI; but it had no obvious effect on INa. Conclusion. The effects of CVB3 on ICa,Iout, IKI may be one of the mechanisms of myocytes damage and the oc-currence of abnormal electroactivities induced by CVB3 infection.     

K~+ Channels and Their Effects on Membrane Potential in Rat Bronchial Smooth Muscle Cells

In order to investigate the K~+ channels and their effects on resting membrane potential(Em) and excitability in rat bronchial smooth muscle cells (BSMCs), the components of outward K~+channel currents and the effects of K~+ channels on Em and tension in rat bronchial smooth musclewere observed by using standard whole-cell recording of patch clamp and isometric tension recordingtechniques. The results showed that under resting conditions, total outward K~+ channel currents infreshly isolated BSMCs were unaffected by ATP-sensitive K~+ channel blocker. There were two typesof K~+ currents: voltage-dependent delayed rectifier K~+ channel (Kv) and large conductance calcium-activated K~+ channel (BK_(Ca)) currents. 1 mmol/L 4-aminopyridine (4-AP, an inhibitor of Kv)caused a significant depolarization (from — 8.7±5.9mV to —25.4±3.1mV, n=18, P<0.001).In contrast, 1 mmol/L tetraethylammonium (TEA, an inhibitor of BK_(Ca)) had no significant effect onEm (from —37.6±4.8 mV to —36.8±4.1 mV, n=12, P>0.05). 4     

K<Superscript>+</Superscript> channels and their effects on membrane potential in rat bronchial smooth muscle cells

Summary In order to investigate the K⁺ channels and their effects on resting membrane potential (Em) and excitability in rat bronchial smooth muscle cells (BSMCs), the components of outward K⁺ channel currents and the effects of K⁺ channels on Em and tension in rat bronchial smooth muscle were observed by using standard whole-cell recording of patch clamp and isometric tension recording techniques. The results showed that under resting conditions, total outward K⁺ channel currents in freshly isolated BSMCs were unaffected by ATP-sensitive K⁺ channel blocker. There were two types of K⁺ currents: voltage-dependent delayed rectifier K⁺ channel (K_v) and large conductance calcium-activated K⁺ channel (BK_Ca) currents. 1 mmol/L 4-aminopyridine (4-AP, an, inhibitor of K_V) caused a significant depolarization (from −8.7±5.9 mV to −25.4±3.1 mV,n=18,P<0.001). In contrast, 1 mmol/L tetraethylammonium (TEA, an inhibitor of BK_Ca) had no significant effect on Em (from −37.6±4.8 mV to −36.8±4.1 mV,n=12,P>0.05). 4-AP caused a concentration-dependent contraction in resting bronchial strips. TEA had no effect on resting tension, but application of 5 mmol/L TEA resulted in a left shift with bigger pD₂ (the negative logarithm of the drug concentration causing 50% of maximal effect) (from 6.27±0.38 to 6.89±0.54,n=10,P<0.05) in the concentration-effect curve of endothine-1, and a right shift with smaller pD₂ (from 8.10±0.23 to 7.69±0.08,n=10,P<0.05) in the concentration-effect curve of isoprenaline. It was suggested that in rat BSMCs there may be two types of K⁺ channels, K_v and BK_Ca, which serve distinct roles. K_v participates in the control of resting Em and tension. BK_Ca is involved in the regulation of relaxation or contraction associated with excitation. LIU Xiansheng, male, born in 1969, M. D., Ph. D. This project was supported by a grant from the National Natural Sciences Foundation of China (No. 30270583).     

Expression and fuactional role of HERG1, K<Superscript>+</Superscript> channels in leukemic cells and leukemic stem cells

Summary In order to investigate the expression and functional role of HERG1 K⁺ channels in leukemic cells and leukemic stem cells (LSCs), RT-PCR was used to detect the HERG1 K⁻ channels expression in leukemic cells and LSCs. The functional role of HERG1 K⁺ channels in leukemic cell proliferation was measured by MTT assay, and cell cycle and apoptosis were analyzed by flow cytometry. The results showed that herg mRNA was expressed in CD34⁺/CD38⁻, CD123⁻ LSCs but not in circulating CD34⁺ cells. Herg mRNA was also up-regulated in leukemia cell lines K562 and HL60 as well as almost all the primary leukemic cells while not in normal peripheral blood mononuclear cells (PBMNCs) and the expression of herg mRNA was not associated with the clinical and cytogenetic features of leukemia. In addition, leukemic cell proliferation was dramatically inhibited by HERG K⁺ channel special inhibitor E-4031. Moreover, E-4031 suppressed the cell growth by inducing a specific block at the G1/S transition phase of the cell cycle but had no effect on apoptosis in leukemic cells. The results suggested that HERG1 K⁺ channels could regulate leukemic cells proliferation and were necessary for leukemic cells to proceed with the cell cycle. HERG1 K⁺ channels may also have oncogenic potential and may be a biomarker for diagnosis of leukemia and a novel potential pharmacological target for leukemia therapy. LI Huiyu, female, born in 1960, Associate Professor This project was supported by a grant from National Science Foundation for Distinguished Young Scholars of China (No. 30225038).     

HEK293细胞内源性电压门控钾离子通道电生理学特性研究

目的探讨人胚胎肾细胞(HEK293细胞)内源性电压门控钾通道的电生理特性,避免HEK293细胞上内源性离子通道对外源性离子通道表达时的干扰。方法利用全细胞膜片钳技术分析了HEK293细胞内源性电压门控钾通道的电生理特性。结果在HEK293细胞上去极化电压从-80 mV开始可触发1个外向电流。在+100 mV时电流为(422.78±68.87)pA,电流密度为(21.91±3.20)pA/pF。钾通道阻断剂四乙胺(tetraethylammonium,TEA)、4-氨基吡啶(4-aminopyri-dine,4-AP),在将细胞外液钾浓度由4 mmol/L提高到40 mmol/L时,对外向电流有影响。结论正常培养的HEK293细胞本身有内源性的钾通道。该外向电流可能包括了IK、IK1、IKur和Ito。     

Differential effects ofd, l-Sotalol andd-Sotalol on isoproterenol-increased delayed rectifier outward potassium current in guinea pig single ventricular myocytes

Summary The aim of this study was to compare the effects ofd, l-Sotalol andd-Sotalol on the delayed rectifier K⁺ outward current in the presence of isoproterenol at different concentrations. Time-dependent delayed rectifier K⁺ outward currents were measured in isolated guinea pig single myocytes using the whole-cell configuration of the patch-clamp technique. Currents were measured in response to 300 ms depolarizing pulses from a holding potential of −40 mV in three experimental protocols [control, isoproterenol (10^-9mollL-10^-6 mollL), and isoproterenol (10^-9mollL-10^-6mollL) plus eitherd, l-Sotalol (10^-4 mollL) ord-Sotalol (10^-4 mollL)]. I_k tail currents were measured upon repolarization to −40 mV. It was found that Ik was significantly amplified in the presence of isoproterenol (10^-9 mollL-10^-6 mollL) plusd-Sotalol. At 10^-8 mollL isoproterenol, I_k was increased by 92. 7%± 17. 1% (P<0. 05) and 54. 3 %±13. 4% afterd-Sotalol addition (P<0. 05). In contrast,d, l-Sotalol completely conteracted the increase of I_k by isoproterenol (<10^-8 mollL), and compared to control, Ik was decreased by 35. 6%± 8. 1 % at 10^-8 mollL isoproterenol plusd, l-Sotalol (P<0. 05). It is concluded that the β-adrenergic blocking property ofd, l-Sotalol but not that ofd-Sotalol maintains the delayed rectifier K⁺ outward current blockade in the presence of isoproterenol in guinea pig myocytes. This might contribute to a superior antiarrhythmic efficacy as compared tod-Sotalol.     

Apoptosis of Leukemia Cells Induced by CD34^＋ Cells Transferred Exogenous Fas Ligand

Summary To assess the value of CD34⁺ cells transferred exogenous Fas ligand (FasL) in inducing apoptosis of human leukemic cells, the CD34⁺ cells transfected with FasL or without, pretreated with mitomycin C, was mixed with leukemic cell line U937 cells in presence or absence of daunorubicin (DNR) or cytosine arabinoside (Ara-C). After 18 h, apoptosis of cells was detected by FCM and TUNEL. Induced for 18 h by CD34⁺ cells transfected with FasL or without, the ratio of apoptosis of U937 cells was (5.0±1.3)%, (10.8±0.6)% (P<0.01), respectively. Induced by FasL⁺CD34⁺+DNR, FasL⁺CD34⁺+Ara-C, the ratio was (13.4±1.0) % (P<0.05), (17.9±1.3)% (P<0.01), respectively. The result demonstrated that CD34⁺ cells transfected with exogenous FasL could induce apoptosis of human leukemic cells and showed a cytotoxic synergistic effect when used in combination with chemotherapeutic drugs, suggesting that it was possible to develop a new method in treatment of leukemia. XIAO Juan, Female, born in 1974, Doctor in Charge This project was supported by the grant of National Nature Science Foundation of China (Serial No. 39770767).     

Use of rats mesenchymal stem cells modified with mHCN2 gene to create biologic pacemakers

The possibility of rats mesenchymal stem cells (MSCs) modified with murine hyperpolarization-activated cyclic nucleotide-gated 2 (mHCN2) gene as biological pacemakers in vitro was studied. The cultured MSCs were transfected with pIRES2-EGFP plasmid carrying enhanced green fluorescent protein (EGFP) gene and mHCN2 gene. The identification using restriction enzyme and sequencing indicated that the mHCN2 gene was inserted to the pIRES2-EGFP. Green fluorescence could be seen in MSCs after transfection for 24-48...     

体外培养视网膜神经元电压门控钾离子通道特性的研究

目的探讨体外培养不同时期新生小牛视网膜神经元电压门控钾离子通道的特性。方法分别取培养2、4、6周的视网膜神经元,进行全细胞膜片钳记录,并进行统计学分析。结果去极化刺激可诱导3组细胞产生IK电流,各组检出率差异无统计学意义(P>0.05);随培养时间延长,IK电流平均峰值增高(P<0.05)。超极化刺激可诱导培养6周的部分细胞产生内向整流钾电流。结论体外培养新生小牛视网膜神经元表达不同电压门控钾电流。某些神经元的电生理学特性在不同培养阶段发生变化。     

维胃方对胃溃疡大鼠胃黏膜MPO、H+-K+-ATP酶活性的影响

[目的]观察维胃方对胃溃疡大鼠胃黏膜髓过氧化物酶(MPO)和H⁺-K⁺-ATP酶的影响,探讨维胃方治疗胃黏膜损伤的可能机制。[方法]采用乙酸烧灼法,建立胃溃疡模型,用比色法测定胃黏膜MPO和H⁺-K⁺-ATP酶活性,并观察胃黏膜组织病理学变化。[结果]从胃黏膜大体标本、切片观察,维胃方中剂量组疗效最佳。与自愈组和模型组比较,维胃方各组胃黏膜MPO活性显著降低(P<0.01或P<0.05),其中以维胃方中剂量组值最小。维胃方各剂量组的H⁺-K⁺-ATP酶活性均高于自愈组(P<0.01或P<0.05),接近正常组(P>0.05),表明维胃方能恢复其活性。[结论]维胃方对大鼠实验性胃溃疡具有明显的保护作用,其机制可能是通过降低大鼠胃黏膜MPO活性,进而减轻炎症介质对胃黏膜的损伤。同时其能修复已损伤的胃黏膜,故能恢复H⁺-K⁺-ATP酶活性。     

Changes of CD4＋ CD25＋ Regulatory T Cells in Peripheral Blood in Patients with Hepatocellular Carcinoma Before and after TACE

This study investigated the changes of CD4＋ CD25＋ regulatory T cells （Tregs） in periph-eral blood of patients with hepatocellular carcinoma before and after transcatheter arterial chemoem-bolization （TACE）. The proportion of CD4＋ CD25＋ Tregs among CD4＋ T lymphocytes in peripheral blood of 33 patients with hepatocellular carcinoma was determined by flow cytometry before, 1 week and 1 month after TACE. And 25 healthy volunteers served as control. One month after TACE, the patients were divided into two groups： 22 in group A, who were in stable condition or getting better; and 10 in group B, who were deteriorating. One patient died and was excluded. The results showed that the percentage of CD4＋CD25＋ Tregs among CD4＋ T lymphocytes did not significantly change in the 33 patients 1 week after TACE as compared with that before TACE, however, the difference was significant （P〈0.01） between the patients with hepatocellular carcinoma and the healthy subjects. The percentage of CD4＋ CD25＋ Tregs among CD4＋ T lymphocytes in group A 1 month after TACE was decreased significantly in comparison with that before and 1 week after TACE （P〈0.01）, whereas, that in group B was increased significantly 1 month after TACE （P〈0.01）. It was concluded that patients with hepatocellular carcinoma had a higher proportion of CD4＋CD25＋ Tregs in peripheral blood. TACE did not significantly affect the level of CD4＋ CD25＋ Tregs within short time （such as 1 week）. The proportion of CD4＋CD25＋ Tregs in peripheral blood 1 month after TACE was related to the prognosis of hepatocellular carcinoma.     

Effect of Interleukin-1β on IA and IK Currents in Cultured Murine Trigeminal Ganglion Neurons

To investigate the effect of interleukin-1β (IL-1β) on IA and IK currents in cultured murine trigeminal ganglion (TG) neurons, whole-cell patch clamp technique was used to record the IA and IK currents before and after 20 ng/mL IL-1β perfusion. Our results showed that 20 ng/mL IL-1β inhibited IA currents (18.3±10.7)% (n=6, P<0.05). IL-1β at 20 ng/mL had no effect on G-V curve of IA but moved the H-infinity curve V0.5 from -36.6±6.1 mV to -42.4±5.2 mV (n=5, P<0.01). However, 20 ng/mL IL-1β had effect on neither the amplitude nor the G-V curve of IK. IL-1β was found to selec- tively inhibit IA current in TG neurons and the effect may contribute to hyperalgesia under various in- flammatory conditions.