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Objective To investigate the effect of alizarin on BKCa channel beta subunit and electrophysiological characteristics in interlobar renal artery of SHR.Methods Tail artery pressure measurement instrument,pressure myograph system,whole cell patch clamp technique and Western blot were used to measure the change of systolic pressure of SHR,renal interlobar arterial diameter,single vascular smooth muscle cell electrophysiological characteristics and expression of the BKCa channel beta subunit before and after alizarin intervention,respectively.Results (1) SHR systolic pressure was decreased after alizarin intervention (P ＜ 0.01).(2) ibTX inhibited alizarin-mediated renal interlobar arterial relaxation (P ＜ 0.01).(3) Alizarin enhanced BKCa channel-mediated outward currents (P ＜ 0.05).(4) Alizarin up-regulated BKCa channel beta subunits after alizarin intervention (P ＜ 0.01).Conclusion Alizarin reduced SHR systolic pressure and relaxed interlobar renal artery by enhancement BKCa currents via mediation of the function of beta subunits.
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Aim To investage the regulatory effect of alizarin on renal interlobar arterial smooth muscle cells. Method The effect of alizarin on BKCa channels was observed by whole-cell patch clamp recording tech-nique. Results Selective BKCa channel blocker ibTX inhibited alizarin-induced outward current(P<0. 05);single smooth muscle cells were incubated in extracel-lular fluid with no Ca2+ 30 minutes, selective L-Ca2+channel blocker nimodipine, selective calcium ion che-lating agent BAPTA-AM and ryanodine inhibited the a-lizarin-induced BKCa channels current, too ( P <0. 05 ) . Conclusion Alizarin relaxes renales interlobar arterial smooth muscle via activation of L-Ca2+ channel firstly, which lead to Ca2+ flowed into cytoplam, and rising of Ca2+ in cytoplam ryanodine receptor indirect-ly, and BKCa is activated at last.
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Objective To investigate the feasibility of serum cardiac troponin T(cTnT) as a marker of cardiovascular events and hemodialysis (HD) adequacy in maintainence hemodialysis (MHD) patients.Methods Forty-seven cases of MHD patients were randomly divided into two groups (group A and group B).Group A received intermittent HD 4 h thrice one week,and group B received intermittent HD 4 h twice one week plus high-flux hemodiafiltration(HDF) 4 h once one week.Serum examination for blood biochemical indicator,cTnT and echocardiogram was performed every three months and at the time of recruitment.All the patients were followed up until the occurrence of death or cardiovascular events.Results After 3 months treatment,serum cTnT deceased significantly in group B compared with group A,and maintained the lower levels throughout the follow-up.E/A and LVEF had been reduced since 3 months treatment in group A,but stable in group B,E/A was lower in group A after 18 months treatment than that in group B,LVEF was lower in group A after 12 months treatment than that in group B.There were positive correlations between cTnT and E/A or LVEF in 42 cases who accomplished the follow-up of 12 months (r =0.54,0.66,P ＜0.05).Kaplan-Meier survival curve showed that the occurrence of cardiovascular events in patients with cTnT≥0.1μ g/L was higher than that with cTnT ＜0.1 μg/L in (28.5 ± 9.7) months' follow- up (Log-rank test: P =0.02).Both survival analysis and Cox analysis indicated that serum cTnT was a predictor of cardiovascular events in MHD patients.Conclusions Serum level of cTnT can be used as a marker of HD adequacy,and it is a predictor of cardiac events in MHD patients.Regular high-flux HDF increases the adequacy of HD treatment and improves the quality of life in MHD patients.