绞股蓝总皂苷对血管性痴呆大鼠海马一氧化氮合酶阳性神经元及核酸的保护作用研究

背景绞股蓝对实验性脑缺血大鼠具有脑保护功能,血管性痴呆大鼠同样具有海马神经元的缺血缺氧性损伤,绞股蓝对此是否也有保护作用? 目的观察绞股蓝总皂苷( gypenosides, GP)对血管性痴呆( vascular dementia,VD)大鼠海马神经元型一氧化氮合酶( neuronal nitric oxide synthase, nNOS)阳性神经元及核酸的保护作用.设计随机对照研究. 地点和对象研究在武警医学院中心实验室进行 ,二级雄性wistar大鼠 30只,体质量 240～ 260 g,由天津市医学实验动物中心提供.干预采用随机数字法将 30只雄性大鼠分为对照组、模型组及给药组.模型组用改进的Pulsinelli 4-血管阻断方法建立大鼠 VD模型.给药组灌胃给药 GP 200 mg/kg,按照大鼠VD模型的制备方法进行手术.对照组同样进行手术但不灼烧颈动脉,不夹闭颈总动脉.主要观察指标①大鼠海马 nNOS表达.②大鼠海马 DNA和 RNA荧光染色强度.结果模型组大鼠海马 CA1区和 CA3区 nNOS阳性神经元数分别为( 20.47±4.22)个和( 25.47± 3.52)个,明显少于对照组 [(24.73± 5.72)和( 37.13± 5.10)个]( P< 0.05), DNA和 RNA吖啶橙染色后的荧光强度(反映 DNA和 RNA含量)也明显减弱.给药组海马CA1区和 CA3区 nNOS阳性神经元数分别为( 30.00± 3.63)个和( 38.00± 5.00)个,比模型组明显增多(P< 0.001);给药组海马 DNA和 RNA吖啶橙染色后的荧光强度强于模型组,且与对照组相似.结论 GP可明显增强血管性痴呆大鼠海马 nNOS阳性神经元的表达,对海马神经元DNA和 RNA损伤有保护作用.

Protective effects of gypenosides on positive neurons of nitric oxide synthase and nucleic acids in hippocampus of rats with vascular dementia

BACKGROUND:Gypenosides（ GP） has a protective effect on the brain of experimental rats with cerebralischemia,but whether it has the same effect on rats with vascular dementia(VD) for the rats also have ischemic-hypoxia injury in the neurons of hippocampus? OBJECTIVE： To observe the protective effect of GP on the positive neurons of neuronal nitric oxide synthase（ nNOS） and the nucleic acid in hippocampus of VD rats. DESIGN： A randomized control study. SETTING and MATERIALS： Study were carried out in the Central Laboratory of Medical college of CPAPF.A total of 30 male rats of grade two,with a body mass from 240 g to 260 g,were purchased from Medical Experimental Animal Center of Tianjin. INTERVENTIONS： Thirty male rats weighing 240 g to 260 g were divided by random number table into control group， model group,and drug group. Modified Pulsinelli's 4-vessel occlusion（ 4-VO） method was used to establish VD rat models.Drug group:GP(200 mg/kg) were filled into stomach and operation was made according to the establishing method of VD rat models.Control group:The same operation was made but without burning the vertebral artery and occluding the general artery. MAIN OUTCOME MEASURES：① the expression of nNOS in hippocampus of rats.② the intensity of fluorescence staining of DNA and RNA in hippocampus of rats. RESULTS： In the model group， the numbers of nNOS positive neurons in CA1 and CA3 fields of hippocampus were 20.47± 4.22 and 25.47± 3.52， which were significantly less than those in the control group(24.73± 5.72 and 37.13± 5.10,respectively)（ P< 0.05） and the fluorescent intensity of the DNA and RNA after acridine orange(AO) staining（ reflecting DNA and RNA contents） also decreased significantly.In the drug group， the numbers of nNOS positive neurons in hippocampus CA1 and CA3 fields were 30.00± 3.63 and 38.00± 5.00 respectively, which increased significantly than those in the model group（ P< 0.001),while the fluorescent intensity of the DNA and RNA after AO staining in the drug group was stronger than that of the model group,which was similar to that of the control group. CONCLUSION:GP can increase the expression of nNOS positive neurons in hippocampus of VD rats significantly.It has a protective effect on DNA and RNA injury of neurons in hippocampus.