地塞米松对大鼠孤束核压力感受性神经元微电泳NA/NPY所致反应的影响  

INFLUENCE OF DEXAMETHASONE ON THE RESPONSES OF BARORECEPTIVE NEURONS IN NUCLEUS TRACTUS SOLITARIUS TO MICROIONTOPHORESIS OF NORADRENALINE/NEUROPEPTIDE Y IN RATS

作　　者：欧阳明[1] 吴绥生[2] 李继安 王绍[1] 

机构地区：[1]白求恩医科大学生理学教研室,长春130021 [2]白求恩医科大学第一临床学院,长春130021 [3]长春绿园区中医院,长春130062

出　　处：《动物学报》2000年第1期58-63,共6页ACTA ZOOLOGICA SINICA

摘　　要：实验采用多管微电泳记录神经元胞外放电技术 ,观察地塞米松 (Dex)、去甲肾上腺素 (NA)及神经肽Y (NPY)对孤束核 (NTS)压力感受反射性神经元的作用 ,以及将这些神经元用Dex预处理后对NA/NPY反应的变化。向NTS内 38个压力感受神经元微电泳Dex后 ,压力感受兴奋性神经元主要表现为抑制 (8/ 19) ,压力感受抑制性神经元则主要表现为兴奋 (9/ 19)。而电泳NA或NPY ,压力感受兴奋性神经元以兴奋反应为主 (10 / 19或 13/ 19) ,抑制反应神经元则以抑制反应为主 (15 / 19或 14/ 19)。如果向那些对NA或NPY有反应的压力感受神经元 (32或 34个单位 )先电泳Dex ,接着电泳NA或NPY ,这些神经元则以无反应为主 (2 0 / 32或 18/ 34 )。由此说明不仅Dex本身快速影响NTS压力感受反射神经元的活动 。The responses of a single neuron in the nucleus tractus solitarius to activation of the baroreflex and to microiontophoresis of Dex, NA or NPY were studied. Of the 75 cells studied, 19 exhibited decrease and another 19 units showed increase in firing rate in response to baroreflex activation, while the remaining 37 neurons showed no response. Microiontophoresis of Dex had exciting effect on baroreflex inhibited cells (9/19) and inhibitory effect on baroreflex excited cells (8/19). In contrast, microiontophoresis of NA or NPY showed inhibitory effect on baroreflexinhibited cells (10/19 or 13/19) and exciting effect on baroreflex excited cells (15/19 or 14/19). The responses of baroreceptive cells to microiontophoresis of NA or NPY were blocked by microiontophoresis of Dex (20/32 or 18/34). The results suggest that Dex has not only a rapid influence on the response of baroreceptive neurons in the NTS, but also a rapid modulation on the response of baroreceptive neurons in the NTS to NA/NPY.

关 键 词：地塞米松 孤束核 微电泳 压力感受性神经元 

分 类 号：Q42[生物学—神经生物学]