The effects of ATP-sensitive mitochondrial K + channel(mitoK ATP) on mitochondrial membrane potential(Δψm),cell proliferation and protein kinase C alpha(PKCα) expression in airway smooth muscle cells(ASMCs) were in...The effects of ATP-sensitive mitochondrial K + channel(mitoK ATP) on mitochondrial membrane potential(Δψm),cell proliferation and protein kinase C alpha(PKCα) expression in airway smooth muscle cells(ASMCs) were investigated.Thirty-six Sprague-Dawley(SD) rats were immunized with saline(controls) or ovalbumin(OVA) with alum(asthma models).ASMCs were cultured from the lung of control and asthma rats.ASMCs were treated with diazoxide(the potent activator of mitoK ATP) or 5-hydroxydencanote(5-HD,the inhibitor of mitoK ATP).Rhodamine-123(R-123) was used to detect Δψm.The expression of PKCα protein was examined by using Western blotting,while PKCα mRNA expression was detected by using real-time PCR.The proliferation of ASMCs was measured by MTT assay and cell cycle analysis.In diazoxide-treated normal ASMCs,the R-123 fluorescence intensity,protein and mRNA levels of PKCα,MTT A values and percentage of cells in S phase were markedly increased as compared with untreated controls.The ratio of G 0 /G 1 cells was decreased(P<0.05) in diazoxide-treated ASMCs from normal rats.However,there were no significant differences between the ASMCs from healthy rats treated with 5-HD and the normal control group.In untreated and diazoxide-treated ASMCs of asthmatic rats,the R-123 fluorescence intensity,protein and mRNA levels of PKCα,MTT A values and the percentage of cells in S phase were increased in comparison to the normal control group.Furthermore,in comparison to ASMCs from asthmatic rats,these values were considerably increased in asthmatic group treated with diazoxide(P<0.05).After exposure to 5-HD for 24 h,these values were decreased as compared with asthma control group(P<0.05).In ASMCs of asthma,the signal transduction pathway of PKCα may be involved in cell proliferation,which is induced by the opening of mitoK ATP and the depolarization of Δψm.展开更多
Objective： To investigate the expression of hergl gene in tumor tissues from gastric carcinomas and gastric carcinoma cell lines, and study the relationship between HERG K＋ channel expressions and tumor cell prolife...Objective： To investigate the expression of hergl gene in tumor tissues from gastric carcinomas and gastric carcinoma cell lines, and study the relationship between HERG K＋ channel expressions and tumor cell proliferation and apoptosis. Methods： RT-PCR and PCR assays were used to detect the expression of hergl gene in 64 gastric carcinomas and the gastric cancer cell line SGC-7901. Blocking the HERG K＋ channels was used to evaluate their effects on tumor cell proliferation and apoptosis. Results：The statistically significant expression of hergl gene was detected in all the gastric cancers and SGC-7901 cells, but not in normal tissues. The HERG K＋ channel blocker, E-4031, increased the cell population in G0/G1（P 〈 0.05） and the number of apoptotic tumor cells（P 〈 0.05）. Conclusion： HERG K＋ channels were expressed in all gastric carcinomas tested and these channels appear to modulate tumor cell proliferation and apoptosis.展开更多
基金supported by grants from Natural Science Foundation of Hubei Province,China (No. 2010CDB096)the National Key Technology R&D Program of the 12th National Five-year Development Plan of China (No. 2012BAI05B01)
文摘The effects of ATP-sensitive mitochondrial K + channel(mitoK ATP) on mitochondrial membrane potential(Δψm),cell proliferation and protein kinase C alpha(PKCα) expression in airway smooth muscle cells(ASMCs) were investigated.Thirty-six Sprague-Dawley(SD) rats were immunized with saline(controls) or ovalbumin(OVA) with alum(asthma models).ASMCs were cultured from the lung of control and asthma rats.ASMCs were treated with diazoxide(the potent activator of mitoK ATP) or 5-hydroxydencanote(5-HD,the inhibitor of mitoK ATP).Rhodamine-123(R-123) was used to detect Δψm.The expression of PKCα protein was examined by using Western blotting,while PKCα mRNA expression was detected by using real-time PCR.The proliferation of ASMCs was measured by MTT assay and cell cycle analysis.In diazoxide-treated normal ASMCs,the R-123 fluorescence intensity,protein and mRNA levels of PKCα,MTT A values and percentage of cells in S phase were markedly increased as compared with untreated controls.The ratio of G 0 /G 1 cells was decreased(P<0.05) in diazoxide-treated ASMCs from normal rats.However,there were no significant differences between the ASMCs from healthy rats treated with 5-HD and the normal control group.In untreated and diazoxide-treated ASMCs of asthmatic rats,the R-123 fluorescence intensity,protein and mRNA levels of PKCα,MTT A values and the percentage of cells in S phase were increased in comparison to the normal control group.Furthermore,in comparison to ASMCs from asthmatic rats,these values were considerably increased in asthmatic group treated with diazoxide(P<0.05).After exposure to 5-HD for 24 h,these values were decreased as compared with asthma control group(P<0.05).In ASMCs of asthma,the signal transduction pathway of PKCα may be involved in cell proliferation,which is induced by the opening of mitoK ATP and the depolarization of Δψm.
基金supported by a grant from the Natural Science Foundation of China(30772128)
文摘Objective： To investigate the expression of hergl gene in tumor tissues from gastric carcinomas and gastric carcinoma cell lines, and study the relationship between HERG K＋ channel expressions and tumor cell proliferation and apoptosis. Methods： RT-PCR and PCR assays were used to detect the expression of hergl gene in 64 gastric carcinomas and the gastric cancer cell line SGC-7901. Blocking the HERG K＋ channels was used to evaluate their effects on tumor cell proliferation and apoptosis. Results：The statistically significant expression of hergl gene was detected in all the gastric cancers and SGC-7901 cells, but not in normal tissues. The HERG K＋ channel blocker, E-4031, increased the cell population in G0/G1（P 〈 0.05） and the number of apoptotic tumor cells（P 〈 0.05）. Conclusion： HERG K＋ channels were expressed in all gastric carcinomas tested and these channels appear to modulate tumor cell proliferation and apoptosis.
