This study is to explore the activation of the Ca2+/CaM/CaN signal pathway in 5-HT-induced proliferation of rat pulmonary artery smooth muscle cells (PASMCs) and the inhibitory effect of m-nisoldipine (m-Nis) on this pathway. PASMCs were cultured with the explant technique. The proliferation of PASMCs was evaluated by MTT assay. Confocal microscopy was used to measure the change of [Ca2+]i. The mRNA expression of CaM and CaN was evaluated by RT-PCR and the activity of CaN was measured according to the instruction of kits. The results of MTT assay suggested that 5-HT (1 ?mol?L-1) significantly induced the proliferation of rat PASMCs (P

Effect of new calcium antagonist m-nisoldipine (m-Nis) on MCT-induced PH in rats and its mechanisms were investigated. Rats were injected with a single doxe(60mg·kg-1)of MCT subcutaneously to induce PH. Pulmonary haemedynamic measurement and lung tissue morphological investigations were undertaken. The MDA production and SOD activity in the serum were tested. PCNA,ERK1 and p-ERK expressions were analyzed by Western blotting. The expressions of 5-HT and PCNA were observed with immunohistochemistry. Results suggested that the PAP, right ventricular index and the degree of muscularization of small pulmonary artery were elevated markedly in MCT group, which was attenuated by m-Nis treatment. A significant reduction in MDA production and an increase in the SOD activity in the serum were also observed in all three m-Nis groups. The number of PCNA and 5-HT positive smooth muscle cells increased significantly in MCT group, and m-Nis treatment attenuated the expression obviously. Western blotting results suggested that the protein expression of PCNA and the ratio of p-ERK/ERK1 increased markedly in MCT group and decreased by m-Nis. In conclusion, m-Nis protected against MCT-induced PH by decreasing PAP, right ventricular index, PAMSCs proliferation and pulmonary artery remodelling, which may be related to the reduction of 5-HT and the suppression of the ERK/MAPK signal pathway.

This study is to explore the activation of the Ca2+/CaM/CaN signal pathway in 5-HT-induced proliferation of rat pulmonary artery smooth muscle cells (PASMCs) and the inhibitory effect of m-nisoldipine (m-Nis) on this pathway. PASMCs were cultured with the explant technique. The proliferation of PASMCs was evaluated by MTT assay. Confocal microscopy was used to measure the change of [Ca2+]i. The mRNA expression of CaM and CaN was evaluated by RT-PCR and the activity of CaN was measured according to the instruction of kits. The results of MTT assay suggested that 5-HT (1 micromol x L(-1)) significantly induced the proliferation of rat PASMCs (P < 0.01), which was inhibited obviously by m-Nis (P < 0.05 or P < 0.01). Similarly, m-Nis inhibited 5-HT-induced elevation of [Ca2+]i (P < 0.01). The mRNA expression of CaM, CaN and the activation of CaN were also inhibited by m-Nis at different degrees (P < 0.05 or P < 0.01). Thus, the results of this study suggested that Ca2+/CaM/CaN signal pathway played an important role in 5-HT-induced proliferation of rat PASMCs, the inhibition of m-Nis on proliferation of rat PASMCs may be related to the blockage of Ca2+/CaM/CaN signal pathway by inhibiting the elevation of [Ca2+]i.

AIM To investigate effect of dipfluzine on sodium current (INa+) in isolated single guinea-pig ventricular myocytes. METHODS INa+ was measured by whole cell patch-clamp technique in single isolated guinea-pig ventricular myocytes which were prepared by enzymatic dissociation method. RESULTSCardiac INa+ was elicited by 50-ms pulses to +50 mV from holding potential at -80 mV with a step of +10 mV, which could be blocked completely by tetrodotoxin 10 μmol·L-1. The peak INa+ occurred at about -20 mV and the reversal potential for INa+ was about +30 mV. Dipfluzine inhibited cardiac INa+ in a concentration-dependent manner. The blocking effect of dipfluzine on INa+ was reversible. Dipfluzine suppressed cardiac INa+, without modifying maximum activation potential and reversal potential. The peak of INa+ was decreased by about 46% at -20 mV and shape of I-V curve was not altered by dipfluzine 40 μmol·L-1. Dipfluzine shifted the steady-state inactivation curve of INa+ towards more negative without changing the slope factor and produced very little change in the steady-state activation curve towards more positive. The mean half activation voltage was (-34.9±5.1) mV and slope factor was (6.0±4.8) mV under control condition and (-33.7±3.6) mV and (5.6±2.4) mV following exposure to dipfluzine 40 μmol·L-1. The half inactivation voltage was (-73.0±4.6)mV and slope factor was (4.8±1.8)mV under control condition and (-82.8±7.2)mV and (4.8±1.8)mV following dipfluzine 40 μmol·L-1 treatment. Dipfluzine delayed recovery of cardiac INa+ from inactivation state. The time course of recovery was (36±11) ms in control group and (79±28) ms in dipfluzine 40 μmol·L-1 group. CONCLUSION Dipfluzine inhi- bits cardiac INa+ in a concentration-dependent manner and has higher affinity for the inactivated state than that for resting state of Na+ channels.

AIM To investigate whether dipfluzine (Dip) possesses antiarrhythmic effect on experimental arrhythmias and effect on cytosolic calcium in ventricular myocytes of guinea-pig. METHODS Experimental arrhythmias were induced by strophanthin G infusion through jugular vein in guinea-pigs and by myocardial ischemia-reperfusion (I-R) in rats respectively. Cytosolic calcium concentration ([Ca2+]i) of isolated guinea-pig ventricular myocytes was examined with laser confocal scanning microscope. RESULTSIn guinea-pigs pretreatment with Dip 20 mg·kg-1 increased the dosages of strophanthin G required to induce ventricular premature contraction (VP), ventricular tachycardia (VT), ventricular fibrillation (VF) and cardiac arrest (CA), pretreatment with Dip 10 mg·kg-1 increased the dosages of strophanthin G required to induce VP. In the I-R-induced arrhythmic model of rats, Dip 20 mg·kg-1 decreased the number of rats exhibiting VT, VF and CA, and the number of rats exhibiting VF and CA was decreased by Dip 10 mg·kg-1. Both Dip and verapamil (Ver) decreased [Ca2+]i of the ventricular myocytes in normal Tyrode′s solution. The Ca2+ overload evoked by high extracellular Ca2+ levels was inhibited by Dip and Ver, and the prophylactic effect of Dip was less than that of Ver, while the curative effect of Dip was more obvious than that of Ver. CONCLUSION Dip has antiarrhythmic effect, which is likely related to the modulation on the intracellular calcium homeostasis.

Aim To investigate the effects of dipfluzine(Dip) on proliferation and collagen synthesis in cultured neonatal rat cardiac fibroblasts(CFB)stimulated by angiotensin Ⅱ(AngⅡ),and to explore the action mechanisms of dipfluzine.Methods CFB were treated with AngⅡ to induce fibrosis model.The effect of Dip on proliferation of CFB was observed by MTT coloricmetric assay;synthesis of collagen was observed by the hydroxyproline concentration detemined;cell cycle distribution and PCNA proein were determined with flow cytometer(FCM);The expression of collagenⅠmRNA,collagen Ⅲ mRNA and TGF-?_1 mRNA was examined using semi-quantitative RT-PCR analysis;The protein expression of cPKC? and ERK_1 in CFB was observed by immunohistochemical staining.Results ① Within a concentration coverage,Dip inhibited CFB proliferation and collagen synthesis(P

Objective To investigate the clinical significance of the level of regulatory T(Treg)cells and indoleamine 2,3-dioxygenase(IDO)in HBV-induced hepatocellar cancinoma.Methods 51 cases of HBV-DNA positive primary liver cancer(HCC),44 cases of chronic hepatitis B(CHB),29 cases of cirrhosis and 28 cases of healthy volunteers(control group)were used RT-PCR and flow cytometry to detect the expression of Treg cells and IDO in peripheral blood of each group.Results The expression of IDO mRNA from high to low were HCC group,CHB group,liver cirrhosis group and control group.The control group and the liver cirrho-sis group were lower than the other 2 groups(P<0.01),and the difference between the other groups was sta-tistically significant(P<0.05).Treg counts from high to low were HCC group,cirrhosis group,CHB group and control group.HCC group was significantly higher than that of control group(P<0.05),except for CHB group,Treg cells in each group were statistically significant compared with control group(P<0.05).The cor-relation analysis of expression of IDO mRNA and Treg:r=0.912,P=0.000,indicating that the expression of IDO in peripheral blood was positively correlated with the Treg cells.Conclusion IDO is over expressed in HCC with the high Treg cell level.Treg cells and IDO may associated with hepatocellular carcinoma immune escape mechanisms.

Objective To analysis the change of hip joint in healthy infants by ultrasound,and establish the normal reference value of the developmental dysplasia of the hip(DDH). Methods A total of 8 000 healthy infants from 0 to 24 weeks were collected from the Multi-center study of 10 children′s medical centers. Among them,3 855 infants(2 065 females and 1 790 males) with complete data and follow-up were included in this study. All subjects were divided into 6 groups ( ＜4,4～7,8～11,12～15,16～19 and≥20 weeks group). α angle,femoral head length and width,femoral head coverage ratio by acetabulum ( FHC) were measured in the coronal view on the neutral position;distance from pubis to femoral head ( P-H) and distance from ischium to femoral head ( I-H ) were measured in the transverse view on neutral position;distance from femoral head topubis ( H-P) was measured in the posterolateraltransverse view on the flexion position. The results of each group changes with age were analysised. Results ① The α angle of healthy infants from 0 to 20 weeks were increased with age,the difference among the groups were statistically significant( P ＜0.05),but there was no significant difference between 16～19 and ≥20 weeks group( P ＞0.05). ②The femoral head length and width of all age groups were increased with age,the difference among all the groups was statistically significant( all P ＜0.05). ③ FHC from 0 to 20 weeks were increased with age,the difference among the groups were statistically significant( P ＜0.05) except between 16～19 and ≥20 weeks group( P ＞0.05). ④ The P-H and I-H in all age groups showed no statistically significant ( all P＞0.05). ⑤The H-P of all age groups were increased with age,the difference between the groups were statistically significant(all P ＜0.05).Conclusions The development of hip joints have the certain regular developmental pattern in healthy infants less than 5 months of birth and are relatively constant after birth more than 5 months. The ultrasound normal reference value of the hip joints can be used for the early diagnosis of the DDH.