柴地合方对慢性应激大鼠大脑皮层5-HT1和5-HT2受体功能的调节

目的观察柴地合方对慢性应激抑郁模型大鼠大脑皮层5-HT1受体和5-HT2受体功能的影响,探讨其抗抑郁作用可能的机制.方法应用大鼠慢性应激模型慢性给药,取动物大脑皮层组织,采用放射配基结合法测定皮层5-HT1受体和5-HT2受体的最大结合率(Bmax)和平衡解离常数(Kd).结果慢性应激使大鼠大脑皮层5-HT1、5-HT2受体的Bmax显著升高(P<0.01),提示受体数目增加;柴地合方慢性治疗可使慢性应激抑郁大鼠前额皮层5-HT1、5-HT2受体的Bmax降低(P<0.01),使抑郁大鼠异常增加的受体数目减少.不论模型大鼠或模型治疗大鼠与正常大鼠比较,其Kd值没有显著性差异(P>0.05),提示受体的亲和力并没有受到影响.结论柴地合方可以降低应激大鼠大脑皮层5-HT1、5-HT2受体的数目,这可能是其抗抑郁作用机理之一.

Regulative Effects of Chaidi Integrated Formula on the Functions of Cerebral 5-HT1 and 5-HT2 Receptors in the Rat with Chronic Stress

Objective To observe the effects of Chaidi Integrated Formula (CIF) on the functions of cerebral 5-HT_1 and 5-HT_2 receptors in the rat model of depression due to chronic stress and to investigate the possible anti-depressive mechanism of CIF. Method First,the rat model of depression due to chronic stress was chronically given CIF,and the cortices of the model rats were then separated for detecting the B_ max and K_d of 5-HT_1 and 5-HT_2 receptors by radioligand binding assay. Results The B_ max of 5-HT_1 and 5-HT_2 receptors in the cortices of the model rats was markedly increased ( P <0.01),which implied an increase in the numbers of the receptors;the chronical CIF-administration to the model rats could decrease the B_ max of 5-HT_1 and 5-HT_2 receptors in the frontal cortices ( P <0.01),which implied a decrease in the abnormally increased numbers of the receptors. It was also found that there was no significant difference between the model rats and the normal control rats or between the CIF-treated model rats and the normal control rats concerning the K_d ( P >0.05),implying that the affinity of the receptors was not affected. Conclusion CIF can decrease the numbers of 5-HT_1 and 5-HT_2 receptors in the cortices of the rats with depression due to chronic stress,which may be one of the anti-depressive mechanisms of CIF.