The Effect Of High Glucose On Store-operated Calcium Channel Of Rat Bladder Smooth Muscle Cells

Objective:To explore the effect of high glucose on store-operated calcium channel of rat bladder smooth muscle cells.By simulating the microenvironment in vitro of diabetes cystopathy,we try to study the role of SOCC in BSMCs under the high glucose condition,which may provide a new sign of DCP's etiology and treatment.Methods:The enzyme digestion method was used to separate rat bladder smooth muscle cells.Immunofluorescences method was employed to identify rat bladder smooth muscle cells.According to different culture medium composition and concentration bladder smooth muscle cells after synchronization were divided into 3 groups:normal glucose group,hypertonic mannito group and high glucose group.All cells were loaded by Fluo-4AM.To observe the changes of fluorescence intensity in different groups after activation or inhibition SOCC with CPA or SKF-96365.F1 was the measured value and F0 was the background value.F1/F0 was used to indicate the relative fluorescence intensity.The mRNA expressions of STIM1 and Orai1 were detected with RT-qPCR and the protein expressions of STIM1 and Orai1 were detected with Western blot.Results:We obtained bladder smooth muscle cells successfully.Immunofluorescences were positive in these cells.Confocal microscope results showed that the calcium ion concentration of BSMCs treated with high glucose increased significantly thanhypertonic mannito group and normal glucose group after SOCC was activated(2.105±0.105,P<0.05)and declined significantly than hypertonic mannito group and normal glucose group after SOCC was inhibited(1.610±0.109,P<0.05),there is no significant difference between hypertonic mannito group and normal glucose group(P>0.05).The levels of STIM1 and Orai1 mRNA and protein expressions of the high glucose group were significantly higher than the other two control groups(P<0.05),there is also no significant difference between hypertonic mannito group and normal glucose group(P>0.05).Conclusion:High glucose can activate SOCC of rat bladder smooth muscle cells and enhance the influx of extracellular calcium.This may provide a new way to study the etiology of DCP and treatment of DCP.However,the further research is needed to explore the exact mechanism.