Investigation of the physiological functions of anion channels during the differentiation in stem cells.

我们研究了小鼠胚胎干细胞(MES)和人骨髓间充质干细胞(HMSCs)在向心肌细胞或脂肪细胞分化过程中阴离子通道的生理功能。RT-PCR检测到未分化的MES细胞和hMSCs中均有ClC-3、ClC-4和Bestrophin基因的表达。在膜片钳实验中，可记录到钙激活的外向钾电流(I&lt；Kca&gt；)，但激活的氯电流太小而无法分析。在低渗溶液中可记录到体积敏感的氯电流。我们认为MES细胞中存在阴离子通道，而未分化的hMSCs中存在ClC-3编码的氯电流和hMSCs。我们以前已经在hMSCs中(2003,2004,2005，在细胞钙中)证明了CaI振荡，因此，我们假设CaI可能影响分化过程。当培养液中加入钙通道阻滞剂时，肥胖被抑制，表明CaI在骨髓间充质干细胞向脂肪分化过程中的作用。

We investigated the physiological functions of anion channels in mouse embryonic stem cells (mES) and human bone marrow-derived mesenchymal stem cells (hMSCs) during the differentiation to cardiac myocytes or adiposities. Using RT-PCR, the expression of mRNA for ClC-3, ClC-4 and Bestrophin could be detected in both undifferentiated mES cells and hMSCs. In the patch clamp experiments, Ca^<2+> activated outward K^+ currents (I_<KCa>) could be recorded, however, Ca^<2+> activated chloride currents were too small to analyze. Volume sensitive Cl currents were could be recorded in the hypotonic solutions. We concluded that anion channels exist in mES cells and hMSCs and Cl currents coded by ClC-3 have a function in undifferentiated hMSCs. We have demonstrated Cai oscillations in hMSCS previously (2003, 2004, 2005, in Cell Calcium), therefore, we hypothesize that Cai might affect the differentiation processes. When Ca channel blockers were added in the culture medium, adiposeness were inhibited, indicating the contribution of Cai to the differentiating processes from mesenchymal stem cell to adiposities.