摘要
探明弓形虫感染对大鼠的学习记忆及脑内单胺类神经递质去甲肾上腺素(NE)、多巴胺(DA)、5-羟色胺(5-HT)含量的影响。取40只雄性SD清洁级(220±20)g成年大鼠随机分成4组,即高、中、低感染剂量的弓形虫腹腔感染组(2×107ml、2×105ml、2×103ml各2 ml)和腹腔注射灭菌生理盐水2 ml的正常对照组。感染后进行被动回避试验和Morris水迷宫试验,观察弓形虫感染对大鼠的学习记忆能力等行为学变化。行为学试验结束后,采用高效液相色谱电化学法检测各组大鼠脑内单胺类神经递质NE、DA、5-HT含量。结果表明:弓形虫感染对大鼠的记忆获得没有影响,但高、中剂量弓形虫感染使大鼠的记忆消失早于对照组(P<0.05),低感染剂量对大鼠记忆消失无影响(P>0.05);各感染组大鼠Morris水迷宫测试中逃避潜伏期均明显延长,其距离百分比明显降低(P<0.05);高、中剂量弓形虫感染大鼠脑组织中的NE、5-HT显著降低(P<0.05),而DA则显著升高(P<0.05);低感染剂量大鼠脑内单胺类神经递质含量与对照组的差异不显著(P>0.05)。因此,弓形虫感染可能通过影响脑内单胺类神经递质的合成而降低学习记忆能力。
Fourty SD rats were randomly divided into 4 groups.Control group was injected intraperitoneally with sterilized saline（2 ml）,and other three groups were infected with Toxoplasma gondii tachyzoites（2×107 ml,2×105 ml,2×103 ml,respectively）.After 63 d of infection,passive avoidance tests and Morris water maze tests were carried out to observe such behavior changes as the learning and memory ability.Meanwhile,the monoamine neurotransmitter contents in the Toxoplasma gondii infected rats brain were measured by high performance liquid chromatography-electrochemical detection（HPLCECD）.Results revealed that the memory acquirement in all rats were normal,but memory retention were severely damaged in high-and middle-concentration Toxoplasma gondii infected rats（P0.05）.The escape latency of the rats in Toxoplasma gondii infected groups was significantly greater than that of the control group and the percentage of distance between the quadrants was obviously decreased（P0.05）.The norepinephrine（NE） and 5-hydroxytryptamine（5-HT） contents were decreased significantly,while the level of dopamine（DA） was significantly increased in high-and middle-concentration Toxoplasma gondii infected rats compared with rats in control group（P0.05）.Low-concentration Toxoplasma gondii had no effect on the contents of monoamine neurotransmitter（P0.05）.The learning and memory ability of rats could be decreased by Toxoplasma gondii infection through regulating the levels of monoamine neurotransmitters contents in rats brain.
出处
《江苏农业学报》
CSCD
北大核心
2010年第2期347-351,共5页
Jiangsu Journal of Agricultural Sciences
基金
江苏省卫生厅基金项目(X200739)
江苏省人口与计划生育委员会基金项目(JS2008-02)
关键词
弓形虫感染
学习记忆能力
MORRIS水迷宫
单胺类神经递质
大鼠
Toxoplasma gondii infection
learning and memory capacity
Morris water maze test
monoamine neurotransmitter
rat
