柴胡注射液对噪音所致学习记忆障碍小鼠的改善作用及机制

Effects of chaihu on learning and memory impairment induced by noise in mice

目的观察柴胡注射液对噪音所致学习记忆障碍的改善作用，并初步探讨其机制。方法选择雌雄昆明种小鼠44只随机分为3组：柴胡组小鼠每日一次给予400mg／kg柴胡注射液腹腔注射，噪音组和正常对照组腹腔注射等体积生理盐水。给药后30min后给予柴胡组和噪音组小鼠93dB的噪音4h，连续12d，正常对照组不给噪音。第9天开始，噪音后1h进行Y-迷宫分辨学习，记录其学习和记忆成绩。测完记忆后立即断头取脑，去除小脑和脑干仅留大脑，匀浆后测脑组织中SOD、AchE活性和MDA含量。结果噪音使小鼠学习、记忆成绩[分别为（12．07±2．71）次，（7．13±0．99）次]下降（P〈0．01），脑组织SOD、MDA[分别为（146．13±30．35）nmol／mgprot，（5．62±0．85）nmol／mgprot]活性升高（P〈0．01），而AchE活性[（1．07±0．12））U／mgprot]下降（P〈0．01）；柴胡注射液能逆转噪音所致学习成绩障碍，使小鼠学习、记忆成绩提高（P〈0．01），脑组织SOD、MDA活性下降（P〈0．01），而AchE活性升高（P〈0．01），接近正常水平。结论柴胡注射液能改善噪音所致学习记忆障碍，其机制可能与提高脑组织抗氧化能力和乙酰胆碱酯酶含量有关。

Objective To observe the protective effect of chaihu on impairment of spatial learning and memory by noise on mice, and investigate its mechanism. Methods Totally 44 healthy Kunming mice were randomly divided into 3 groups. The chaihu group was intraperitoneal injection chaihu 400mg/kg everyday, simultane-ously, noise group and blank control group were treated with distilled water by intraperitoneal injection. Half an hour later,chaihu group and noise group were put in 93dB pulse noise for 4 hour and this condition last for 12 days. The blank control group was on normal condition. One hour later after noise, all of groups received Y-maze training. The achievements of learning and memory were recorded. All the mice were killed after behavioral obser-vation . The brain was took apart , the brain stem and cerebellum was removed to measure the content of superoxide dismutase （SOD） , malondialdehyde （ MDA ） and acetylcholinesterase （ Ache ） after homogenate. Results The noise make the achievements of learning and memory decline respectively [（12.07±2.71） times vs （7.13±0.99） times, P 〈 0.01] , the activity of SOD and MDA increased respectively [（146.13±30.35 ） nmol/mgprot vs （5.62±0.85） nmol/mgprot, P 〈 0.01], the activity of Ache was decreased [（1.07±0.12）U/mgprot, P 〈 0.01 ] ;which is parallel to the noise effect on the spatial learning and memory, chaihu can reversed the change of the SOD, MDA and Ache level and improve spatial learning and memory of the model animals. Conclusion The chaihu can improve impairment of spatial learning and memory by noise on mice. The mechanism is related with enhancing the antioxidizing ability and increasing the content of Ache in the brain.