黄连素对大鼠结肠上皮隐窝细胞基底膜钾通道的影响

Effects of bererine on basolateral potassium current of rat colonic crypt cells

目的研究黄连素对结肠上皮隐窝细胞基底膜钙依赖钾通道[I_K(Ca)]和环磷酸腺苷(cAMP)依赖钾通道[I_K(cAMP)]的影响,探讨其治疗分泌性腹泻的机制。方法用乙二胺四乙酸(EDTA)溶液分离结肠上皮隐窝细胞,运用EPC 10膜片钳放大器测量全细胞模式下50、100、500μmol/L黄连素对结肠上皮细胞基底膜I_K(Ca)和I_K(cAMP)的影响,并设PSS对照组。结果50、100、500μmol/L黄连素可抑制大鼠结肠上皮隐窝细胞基底膜I_K(Ca)和I_K(cAMP)(P值均<0.05),当阶跃刺激为+80mV时,其I_K(Ca)分别为对照组的(71.43±3.61)%、(54.56±5.13)%、(38.66±3.85)%(P<0.05);其I_K(cAMP)分别为对照组的(78.55±5.72)%、(60.42±6.33)%、(43.78±6.47)%(P<0.05)。结论黄连素能抑制大鼠结肠上皮细胞基底膜I_K(Ca)和I_K(cAMP)的开放,这可能是其治疗分泌性腹泻的机制之一。

Objective To investigate the effects of berberine on basolateral calcium-activated potassium current IK（Ca） and cAMP-activated potassium current IK（cAMP） and its mechanism in treatment of secretory diarrhea. Methods The intact colonic crypt cells were isolated with EDTA solution. The effects of berberine（50, 100, 500 μmol/L）on IK（Ca） and IK（cAMP） were detected by patch clamp technique under the conventional whole cell patch clamp mode. The solution of PSS was served as control. Results Berberine could significantly inhibite IK（Ca） and IK（cAMP） of rat colonic crypt cells（both P 〈 0.05）in concentrations of 50, 100, 500 μmol/L. When depolarizing at ＋ 80 mV, the inhibitory rates of IK（Ca） were（ 71. 43 ± 3.61）%, （54.56 ± 5. 13） %, （38.66 ± 3.85）% and IK（cAMP） were（78. 55 ± 5. 72）%, （60.42 ± 6. 33）%, （43. 78 ± 6. 47）% at concentration of 50, 100, 500 μmol/L, respectively, compared with control. Conclusion Berberine can inhibit the pathway of IK（Ca） and IK（cAMp） in rat colonic crypt cells, which may be one of the mechanisms in treatment of secretory diarrhea.