高渗刺激后大鼠下丘脑神经元和星形胶质细胞内钙的动态变化

Dynamic changes of intracellular calcium of hypothalamic neurons and astrocytes following hyperosmotic stimulation

目的探讨高渗刺激后大鼠下丘脑神经元和星形胶质细胞(AST)内钙的变化。方法体外联合培养的神经元和AST经钙荧光指示剂Fluo-3负载后,用激光扫描共聚焦显微镜测定高渗NaCl溶液影响前后的细胞内钙水平随时间变化情况。结果高渗刺激使培养神经元和AST内钙水平先升高后降低,最后维持在比高渗刺激前稍高的静息钙水平上。AST钙水平达到峰值的速度略快于神经元。结论神经元和AST内Ca2+在渗透压信息传递过程起作用。

Objective To investigate the changes of intracellular calcium in rat hypothalamic neurons and its astrocytes following hyperosmotic pressure. Methods Intracellular calcium levels were measured with the fluorescent Ca2+ indicator Fluo-3 and laser scanning confocal microscopy in co-cultured neurons and astrocytes following hyperosmotic NaCl solution. Results Treated with heperosmotic NaCl solution, intracellular calcium concentration in cultured hypothalamic neurons and astrocytes increased at the begining and then decreased gradually. At last, it maintained at a little higher level of resting intracellular calcium than before hyperosmotic stimulation. The velocity of astrocytic intracellular calcium elevation to the peak value was a slightly faster than neurons. Conclusion The results indicate calcium in neurons and astrocytes may play a role in the process of osmotic pressure message transmission.