The roles of intermediate conductance Ca2＋-activated K＋ channel （IKCal） in the pathogene- sis of hepatocellular carcinoma （HCC） were investigated. Immunohistochemistry and Western blotting were used to detect th...The roles of intermediate conductance Ca2＋-activated K＋ channel （IKCal） in the pathogene- sis of hepatocellular carcinoma （HCC） were investigated. Immunohistochemistry and Western blotting were used to detect the expression of IKCal protein in 50 HCC and 20 para-carcinoma tissue samples. Real-time PCR was used to detect the transcription level of IKCal mRNA in 13 HCC and 11 para-carcinoma tissue samples. The MTT assay was used to measure the function of IKCal in human HCC cell line HepG2 in vitro. TRAM-34, a specific blocker of IKCal, was used to intervene with the function of IKCal. As compared with para-carcinoma tissue, an over-expression of IKCal protein was detected in HCC tissue samples （P〈0.05）. The mRNA expression level of IKCal in HCC tissues was 2.17 times higher than that in para-carcinoma tissues. The proliferation of HepG2 cells was suppressed by TRAM-34 （0.5, 1.0, 2.0 and 4.0 pxnol/L） in vitro （P〈0.05）. Our results suggested that IKCal may play a role in the proliferation of human HCC, and IKCal blockers may represent a potential therapeutic strategy for HCC.展开更多
Objective: To study the effect of isoflurane and ethanol on large conductance Ca 2+-activated K + channels(BK channels). Methods: The cRNA of mslo1 encoding BK channels was injected into Xenopus oocytes. Oocytes were ...Objective: To study the effect of isoflurane and ethanol on large conductance Ca 2+-activated K + channels(BK channels). Methods: The cRNA of mslo1 encoding BK channels was injected into Xenopus oocytes. Oocytes were incubated in ND96 (96 mmol/L NaCl, 2.0 mmol/L KCl, 1.8 mmol/L CaCl 2, 1.0 mmol/L MgCl 2, and 5.0 mmol/L HEPES, pH 7.4) at 4 ℃. Patch clamp recording (outside-out) were performed after 2-3 d. Isoflurane was administrated by the vaporizer driven by air, ethanol was applied by a closed, manual-controlled administration system. Different test potentials from 0 to 10 mV were given to observe changes of currents. Results: 0.7 mmol/L and 1.2 mmol/L of isoflurane could inhibit BK currents obviously at different command potentials, but 50 mmol/L, 100 mmol/L, or 200 mmol/L of ethanol had no any effect on BK currents. Conclusion: Clinical concentration of isoflurane can distinctly inhibit isolating BK currents.展开更多
The human endogenous retroviruses type W family envelope(HERV-W env)gene is located on chromosome 7q21-22.Our previous studies show that HERV-W env is elevated in schizophrenia and HERV-W env can increase cal-cium inf...The human endogenous retroviruses type W family envelope(HERV-W env)gene is located on chromosome 7q21-22.Our previous studies show that HERV-W env is elevated in schizophrenia and HERV-W env can increase cal-cium influx.Additionally,the 5-HTergie system and particularly 5-hydroxytryptamine(5-HT)receptors play a prominent role in the pathogenesis and treatment of schizophrenia.5-hydroxytryptamine receptor 4(5-HT4R)agonist can block calcium channels.However,the underlying relationship between HERV-W env and 5-HT4R in the etiology of schizophrenia has not been revealed.Here,we used enzyme-linked immunosorbent assay to detect the concentration of HERV-W env and 5-HT4R in the plasma of patients with schizophrenia and we found that there were decreased levels of 5-HT4R and a negative correlation between 5-HT4R and HERV-W env in schizophrenia.Overexpression of HERV-W env decreased the transcription and protein levels of 5-HT4R but increased small conductance Ca^(2+)-activated K^(+)type 2 channels(SK2)expression levels.Further studies revealed that HERV-w env could interact with 5-HT4R.Additionally,luciferase assay showed that an essential region(-364 to-176 from the transcription start site)in the SK2 promoter was required for HERV-W env-induced SK2 expression.Importantly,5-HT4R participated in the regulation of SK2 expression and promoter activity.Electrophysiological recordings suggested that HERV-Wenv could increase SK2 channel currents and the increase of SK2 currents was inhibited by 5-HT4R.In condusion,HERV-W env could activate SK2 channels via decreased 5-HT4R,which might exhibit a novel mechanism for HERV-Wenv to influence neuronal activity in schizophrenia.展开更多
Objective:To study the correlation of large conductance Ca2+ activated K+ channel (BKCa)α andβ subunit expression in uterine smooth muscle with the postpartum hemorrhage induced by uterine inertia.Methods: The puerp...Objective:To study the correlation of large conductance Ca2+ activated K+ channel (BKCa)α andβ subunit expression in uterine smooth muscle with the postpartum hemorrhage induced by uterine inertia.Methods: The puerperae who underwent cesarean section and had postpartum hemorrhage induced by uterine inertia in Panzhihua Women and Children Health Hospital between March 2015 and May 2017 were selected as the hemorrhage group of the study, and the puerperae who underwent cesarean section and were without postpartum hemorrhage in Panzhihua Women and Children Health Hospital during the same period were selected as the control group. Proper amount of uterine muscle tissue was collected during the cesarean section to measure the expression of BKCaα andβ subunits and the levels of contraction-related proteins in uterine muscle as well as the contraction characteristic parameters of the uterine muscle.Results: The mRNA expression and protein expression of BKCaα andβ subunits in uterine muscle tissue of hemorrhage group were significantly higher than those of control group;the contraction amplitude, contraction frequency and contraction activity of uterine muscle tissue as well as the OTR, COX2, CX43 and HSP27 levels in uterine muscle tissue of hemorrhage group were significantly lower than those of control group;the BKCaα andβ subunit expression in uterine muscle tissue of hemorrhage group were negatively correlated with the contraction amplitude, contraction frequency and contraction activity as well as the OTR, COX2, CX43 and HSP27 levels.Conclusion: The high expression of BKCa in uterine smooth muscle can reduce the uterine muscle contractility and decrease the levels of contraction-related proteins, and it is closely related to the occurrence of postpartum hemorrhage induced by uterine inertia.展开更多
TRPV4 activity modulates cell activities including receptor trafficking and transcriptional or translational regulations. We tested its CRISPR/Cas9 scissor efficacy in HepG2 (HEK293) cell noticed that it worked well i...TRPV4 activity modulates cell activities including receptor trafficking and transcriptional or translational regulations. We tested its CRISPR/Cas9 scissor efficacy in HepG2 (HEK293) cell noticed that it worked well in both cell lines to eliminate TRPV4 genome sequences. To confirm TRPV4 functions in the cell morphology maintenance and cell growth (beyond Ca2+ channel), we compared its wound healing, cell surface area, survival property and soft agar growth ability after deletion of TRPV4 gene in the cells with its CRISPR/Cas9 system. With these experiments, we confirmed that TRPV4 is required not only to function as Ca2+ channel but also to maintain its proper cell morphology as a corner stone protein on the cell adhesion junction.展开更多
The present study attempted to test a novel hypothesis that Ca^2＋ sparks play an important role in arterial relaxation induced by tacrolimus. Recorded with confocal laser scanning microscopy, tacrolimus（10 μmol/L）...The present study attempted to test a novel hypothesis that Ca^2＋ sparks play an important role in arterial relaxation induced by tacrolimus. Recorded with confocal laser scanning microscopy, tacrolimus（10 μmol/L） increased the frequency of Ca^2＋ sparks, which could be reversed by ryanodine（10 μmol/L）. Electrophysiological experiments revealed that tacrolimus（10 μmol/L） increased the large-conductance Ca^2＋-activated K＋ currents（BKCa） in rat aortic vascular smooth muscle cells（AVSMCs）, which could be blocked by ryanodine（10 μmol/L）. Furthermore, tacrolimus（10 and 50 μmol/L） reduced the contractile force induced by norepinephrine（NE） or KCl in aortic vascular smooth muscle in a concentration-dependent manner, which could be also significantly attenuated by iberiotoxin（100 nmol/L） and ryanodine（10 μmol/L） respectively. In conclusion, tacrolimus could indirectly activate BKCa currents by increasing Ca^2＋ sparks released from ryanodine receptors, which inhibited the NE- or KCl-induced contraction in rat aorta.展开更多
基金supported by grants from the National Natural Science Foundation of China (No. 81072001)the Natural Science Foundation of Hubei Province, China (No.2011CDB556)
文摘The roles of intermediate conductance Ca2＋-activated K＋ channel （IKCal） in the pathogene- sis of hepatocellular carcinoma （HCC） were investigated. Immunohistochemistry and Western blotting were used to detect the expression of IKCal protein in 50 HCC and 20 para-carcinoma tissue samples. Real-time PCR was used to detect the transcription level of IKCal mRNA in 13 HCC and 11 para-carcinoma tissue samples. The MTT assay was used to measure the function of IKCal in human HCC cell line HepG2 in vitro. TRAM-34, a specific blocker of IKCal, was used to intervene with the function of IKCal. As compared with para-carcinoma tissue, an over-expression of IKCal protein was detected in HCC tissue samples （P〈0.05）. The mRNA expression level of IKCal in HCC tissues was 2.17 times higher than that in para-carcinoma tissues. The proliferation of HepG2 cells was suppressed by TRAM-34 （0.5, 1.0, 2.0 and 4.0 pxnol/L） in vitro （P〈0.05）. Our results suggested that IKCal may play a role in the proliferation of human HCC, and IKCal blockers may represent a potential therapeutic strategy for HCC.
文摘Objective: To study the effect of isoflurane and ethanol on large conductance Ca 2+-activated K + channels(BK channels). Methods: The cRNA of mslo1 encoding BK channels was injected into Xenopus oocytes. Oocytes were incubated in ND96 (96 mmol/L NaCl, 2.0 mmol/L KCl, 1.8 mmol/L CaCl 2, 1.0 mmol/L MgCl 2, and 5.0 mmol/L HEPES, pH 7.4) at 4 ℃. Patch clamp recording (outside-out) were performed after 2-3 d. Isoflurane was administrated by the vaporizer driven by air, ethanol was applied by a closed, manual-controlled administration system. Different test potentials from 0 to 10 mV were given to observe changes of currents. Results: 0.7 mmol/L and 1.2 mmol/L of isoflurane could inhibit BK currents obviously at different command potentials, but 50 mmol/L, 100 mmol/L, or 200 mmol/L of ethanol had no any effect on BK currents. Conclusion: Clinical concentration of isoflurane can distinctly inhibit isolating BK currents.
基金supported by the National Natural Science Foundation of China(Nos.81971943,81772196,31470264,81271820,30870789,and 30300117)the Stanley Foundation from the Stanley Medical Research Institute(SMRI),United States(No.06R-1366)We acknowledge the Medicine Research Center for Structural Biology of Wuhan University for providing the confocal microscopy(Leica-LCS-SP8-STED).
文摘The human endogenous retroviruses type W family envelope(HERV-W env)gene is located on chromosome 7q21-22.Our previous studies show that HERV-W env is elevated in schizophrenia and HERV-W env can increase cal-cium influx.Additionally,the 5-HTergie system and particularly 5-hydroxytryptamine(5-HT)receptors play a prominent role in the pathogenesis and treatment of schizophrenia.5-hydroxytryptamine receptor 4(5-HT4R)agonist can block calcium channels.However,the underlying relationship between HERV-W env and 5-HT4R in the etiology of schizophrenia has not been revealed.Here,we used enzyme-linked immunosorbent assay to detect the concentration of HERV-W env and 5-HT4R in the plasma of patients with schizophrenia and we found that there were decreased levels of 5-HT4R and a negative correlation between 5-HT4R and HERV-W env in schizophrenia.Overexpression of HERV-W env decreased the transcription and protein levels of 5-HT4R but increased small conductance Ca^(2+)-activated K^(+)type 2 channels(SK2)expression levels.Further studies revealed that HERV-w env could interact with 5-HT4R.Additionally,luciferase assay showed that an essential region(-364 to-176 from the transcription start site)in the SK2 promoter was required for HERV-W env-induced SK2 expression.Importantly,5-HT4R participated in the regulation of SK2 expression and promoter activity.Electrophysiological recordings suggested that HERV-Wenv could increase SK2 channel currents and the increase of SK2 currents was inhibited by 5-HT4R.In condusion,HERV-W env could activate SK2 channels via decreased 5-HT4R,which might exhibit a novel mechanism for HERV-Wenv to influence neuronal activity in schizophrenia.
文摘Objective:To study the correlation of large conductance Ca2+ activated K+ channel (BKCa)α andβ subunit expression in uterine smooth muscle with the postpartum hemorrhage induced by uterine inertia.Methods: The puerperae who underwent cesarean section and had postpartum hemorrhage induced by uterine inertia in Panzhihua Women and Children Health Hospital between March 2015 and May 2017 were selected as the hemorrhage group of the study, and the puerperae who underwent cesarean section and were without postpartum hemorrhage in Panzhihua Women and Children Health Hospital during the same period were selected as the control group. Proper amount of uterine muscle tissue was collected during the cesarean section to measure the expression of BKCaα andβ subunits and the levels of contraction-related proteins in uterine muscle as well as the contraction characteristic parameters of the uterine muscle.Results: The mRNA expression and protein expression of BKCaα andβ subunits in uterine muscle tissue of hemorrhage group were significantly higher than those of control group;the contraction amplitude, contraction frequency and contraction activity of uterine muscle tissue as well as the OTR, COX2, CX43 and HSP27 levels in uterine muscle tissue of hemorrhage group were significantly lower than those of control group;the BKCaα andβ subunit expression in uterine muscle tissue of hemorrhage group were negatively correlated with the contraction amplitude, contraction frequency and contraction activity as well as the OTR, COX2, CX43 and HSP27 levels.Conclusion: The high expression of BKCa in uterine smooth muscle can reduce the uterine muscle contractility and decrease the levels of contraction-related proteins, and it is closely related to the occurrence of postpartum hemorrhage induced by uterine inertia.
文摘TRPV4 activity modulates cell activities including receptor trafficking and transcriptional or translational regulations. We tested its CRISPR/Cas9 scissor efficacy in HepG2 (HEK293) cell noticed that it worked well in both cell lines to eliminate TRPV4 genome sequences. To confirm TRPV4 functions in the cell morphology maintenance and cell growth (beyond Ca2+ channel), we compared its wound healing, cell surface area, survival property and soft agar growth ability after deletion of TRPV4 gene in the cells with its CRISPR/Cas9 system. With these experiments, we confirmed that TRPV4 is required not only to function as Ca2+ channel but also to maintain its proper cell morphology as a corner stone protein on the cell adhesion junction.
基金supported by the National Natural Science Foundation of China(No.81102439)
文摘The present study attempted to test a novel hypothesis that Ca^2＋ sparks play an important role in arterial relaxation induced by tacrolimus. Recorded with confocal laser scanning microscopy, tacrolimus（10 μmol/L） increased the frequency of Ca^2＋ sparks, which could be reversed by ryanodine（10 μmol/L）. Electrophysiological experiments revealed that tacrolimus（10 μmol/L） increased the large-conductance Ca^2＋-activated K＋ currents（BKCa） in rat aortic vascular smooth muscle cells（AVSMCs）, which could be blocked by ryanodine（10 μmol/L）. Furthermore, tacrolimus（10 and 50 μmol/L） reduced the contractile force induced by norepinephrine（NE） or KCl in aortic vascular smooth muscle in a concentration-dependent manner, which could be also significantly attenuated by iberiotoxin（100 nmol/L） and ryanodine（10 μmol/L） respectively. In conclusion, tacrolimus could indirectly activate BKCa currents by increasing Ca^2＋ sparks released from ryanodine receptors, which inhibited the NE- or KCl-induced contraction in rat aorta.
