螺旋藻改善铝中毒小鼠学习记忆障碍机制探讨

The mechanism of ameliorative effects of spirulina on learning-memory impairment of mice induced by aluminium

目的:探讨螺旋藻改善铝中毒小鼠学习记忆障碍的作用机制。方法:用口服氯化铝方法建立小鼠铝中毒学习记忆障碍模型,并用螺旋藻多糖灌胃进行实验性治疗。用跳台试验和避暗试验检测各组小鼠的学习记忆行为,并用免疫组化ABC法检测各组小鼠海马神经元型一氧化氮合酶(nNOS)的表达。结果:与对照组比较,模型组小鼠表现出明显的学习记忆障碍,海马nNOS表达下降。实验组的学习记忆能力较模型组有明显改善,海马nNOS表达增加。结论:螺旋藻对铝中毒小鼠的学习记忆障碍有明显的改善作用,其作用机制可能与增加nNOS的表达有关。

AIM:Researches in recent years indicate d that spirulina could improve var-ious aging indexes and the learning-memory impairment of aging-model mi ce induced by aluminium.METHODS :Models of learning-memory impairme nt in mice were prepared with mice orall y taking aluminium(303.3mg /kg each day and 90days on end).In the experimental group,2.0g /kg spirulina was perfused into the mice' s stomaches every day and then through step down test and step through test,the mice' s learning-memory ability in every g roup was evaluated while the nNOS expression of hippocampus was observed through ABC immunohistochemistry method in the model group,the experimental group and the control group.RESULTS:(1)Result of step through test.The evade latent period(EL)of the model group was much longer than that of the control group(P<0.01),while EL of the experimental group wa s obviously shorter than that of the model group(P<0.01);The mistake times(M)in the model group were more than those o f the control group(P<0.05),while there was no difference between the e xperimental group and the control group(P>0.05).(2)Result of the step down test.The evad e latent period of the model group was much longer and the mi stake times(M)of the model group were more than those of the control group(P<0.05).There was no dif-ference in the latent period(L)and mistake times(M)between the model group and the control group in camera obscura(P>0.05).(3)Results of immunohistochemistry staining:th e numerical density on area(NA)and the integral value of optical density(IOD)of nNOS positive cells in hippocampus CA2～3of the model group were obviously decreased than those of the contro l group(P<0.01),while there was no difference betwe en the experimental group and the control group(P>0.05).CONCLUSION:The results indi-cate that spirulina can greatly impr ove the learning-memory impairment of mice induced by aluminium poisoning and its mechanism may be related to increased nNOS expression.