涤痰汤加味方对血管性痴呆大鼠行为学及PKA/CREB 信号通路的影响

目的研究涤痰汤加味方对血管性痴呆(VD)大鼠行为学、大鼠海马PKA/CREB信号通路的影响。方法将120只雄性SD大鼠随机分为空白组和造模组,空白组20只,造模组100只,空白组予普通饲料喂养,造模组以高脂饲料喂养复合颈总动脉结扎制作VD模型,将模型制作成功大鼠随机分为模型组、多奈哌齐组、活血组、涤痰汤原方组、涤痰汤加味组,每组18只,空白组和模型组每天灌胃等量的生理盐水,其他组给予相应药物连续灌胃4周。采用水迷宫检测大鼠的行为学,采用ELISA和Western Blot法检测大鼠海马区PKA/CREB信号通路相关因子表达。结果与空白组比较,模型组大鼠发现平台时间和游泳总路程明显增加(P<0.01)。与模型组比较,各给药组大鼠发现平台时间和游泳总路程均减少(P<0.05,P<0.01)。与涤痰汤原方组比较,活血组发现平台时间和游泳总路程增多(P<0.05,P<0.01),涤痰汤加味组发现平台时间和游泳总路程减少(P<0.05)。与空白组比较,模型组大鼠穿越平台次数、目标象限时间均明显减少(P<0.01),首次抵达平台时间明显延长(P<0.01)。与模型组比较,多奈哌齐组大鼠穿越平台次数增加(P<0.05),首次抵达平台时间明显缩短(P<0.01);涤痰汤原方组、涤痰汤加味组和活血组大鼠穿越平台次数、目标象限时间均增加(P<0.05,P<0.01),首次抵达平台时间明显缩短(P<0.01)。与空白组比较,模型组大鼠海马组织中环磷腺苷(cAMP)、蛋白激酶A(PKA)、环磷腺苷效应元件结合蛋白(CREB)、脑源性神经营养因子(BDNF)、神经生长因子(NGF)含量均明显降低(P<0.01);与模型组比较,各给药组大鼠海马组织内cAMP、PKA、CREB、BDNF、NGF含量均增高(P<0.05,P<0.01)。与涤痰汤原方组比较,活血组大鼠海马中cAMP、PKA、CREB、BDNF、NGF含量均减少(P<0.05,P<0.01),而涤痰汤加味组大鼠海马中cAMP、PKA、CREB、BDNF、NGF含量均增加(P<0.05)。结论涤痰汤加味可以改善VD模型大鼠的学习记忆能力,其机制可能与其激活海马PKA/CREB信号通路有关。

Effect of Modified Ditan Decoction on Behavior and PKA/CREB Signaling Pathway in Vascular Dementia Rats

Objective To study the effect of Modified Ditan Decoction(MDD)on behavior and protein kinase A(PKA)/cyclic adenosine monophosphate(cAMP)-response element binding protein(CREB)signaling pathway in hippocampus of vascular dementia(VD)rats.Methods Totally 120 male SD rats were randomly divided into a blank group(n=20)and a model group(n=100).The rats in the blank group were fed with normal forage.The VD model was established by high fat diet and ligation of common carotid artery.The successfully modeled rats were randomly divided into model group(sham-operation group),donepezil group,Huoxue group,Ditan Decoction group,and MDD group,18 in each group.The same amount of normal saline was daily administered to rats in the blank group and the model group by gastrogavage.Corresponding drugs were administered to rats in the other groups for 4 successive weeks.Behavior was detected by water Morris.Expressions of PKA/CREB related factors in hippocampus were detected by ELISA and Western Blot.Results Compared with the blank group,the platform time and total swimming distance significantly increased in the model group(P<0.01).Compared with the model group,the platform time and the total swimming distance were reduced in each medicated group(P<0.05,P<0.01).Compared with Ditan Decoction group,the platform time and the total swimming distance increased in Huoxue group(P<0.05,P<0.01);the platform time and the total swimming distance were reduced in MDD group(P<0.05).Compared with the blank group,the times of crossing the platform and the target quadrant time were significantly reduced(P<0.01),and the first time to reach the platform was significantly longer(P<0.01)in the model group.Compared with the model group,the times of crossing platforms increased(P<0.05),the first time to reach the platform was significantly shortened(P<0.01)in donepezil group.Compared with the model group,the times of crossing the platform and the target quadrant time increased(P<0.05,P<0.01),and the first time to reach the platform was significantly shortened(P<0.01)in Huoxue group,Ditan Decoction group,and MDD group.Compared with the blank group,the levels of cAMP,PKA,CREB,brain derived neurotrophic factor(BDNF),and nerve growth factor(NGF)in the hippocampus were significantly reduced in the model group(P<0.01).Compared with the model group,the levels of cAMP,PKA,CREB,BDNF,and NGF in the hippocampus significantly increased in each medicated group(P<0.05,P<0.01).Compared with Ditan Decoction group,the levels of cAMP,PKA,CREB,BDNF,and NGF in the hippocampus were reduced in Huoxue group(P<0.05,P<0.01);they increased in MDD group(P<0.05).Conclusions MDD improved the learning and memory ability of VD model rats.Its mechanism might be related to activation of hippocampal PKA/CREB signaling pathway.