雌激素对去卵巢大鼠基底前脑NOS及Nestin阳性神经元的影响

目的 观察雌激素替代对去卵巢大鼠基底前脑一氧化氮合酶(NOS)及巢蛋白(Nestin)阳性神经元的影响。方法 将28只健康成年雄性SD大鼠随机分为4个处理组:去势24 h雌激素替代组、去势2周雌激素替代组、去势植物油替代组及假手术组。用组织化学及免疫组织化学染色方法观察基底前脑的内侧隔核(MS)、斜角带垂直支(vDB)及水平支(hDB)的NOS和Nestin阳性神经元数的变化。结果 去势行植物油替代可使MS、vDB的NOS阳性神经元数明显下降(P<0.01);去势24 h或2周行雌激素替代均可使以上亚区的NOS阳性神经元数明显升高至正常水平(P<0.01)。去势行植物油替代或雌激素替代对hDB的:Nestin阳性神经元数的影响趋势与NOS阳性神经元的相似(P<0.01),但对MS及vDB的Nestin阳性神经元数影响不大(P>0.05)。结论 去卵巢行雌激素替代可选择性地使基底前脑不同亚区NOS、Nestin阳性神经元数升高,这可能与雌激素高调了NOS和Nestin的表达有关。

Changes in nitric oxide synthase immunoreative and nestin immunoreactive neurons of the basal forebrain following estrogen replacement of ovariectomized rats

Objective To investigate the effects of estrogen replacement on nitric oxide synthase(NOS) immunoreactive and nestin immunoreactive(IR) neurons in the basal forebrain of ovariectomized rats. Methods Healthy adult female SD rats were randomly divided into four groups: ovariectomized group ofter 24 hours plus replacement of estradiol benzoate (EB), ovariectomized group after two weeks plus replacement of EB, ovariectomized group after 24 hours plus replacement of sesame oil (SO) and sham group. Histochemical and immunohistochemical techniques were used to count the number of NOS-IR and Nestin-IR neurons in the medial septum(MS) , vertical(vDB) and horizontal(hDB) limbs of the diagonal band of Broca among four groups. Results The numbers of NOS-IR neurons in MS,vDB and hDB of ovariectomized group after 24 hours plus replacement of SO significantly decreased( P < 0.01) , while the numbers of NOS-IR neurons in the three subregions of ovariectomized groups after 24 hours or two weeks plus replacement of EB significantly increased to the levels of sham group ( P < 0.01) . The changes in the number of Nestin-IR neurons in hDB of four groups were similar to those of NOS-IR neurons, but the numbers of Nestin-IR neurons in MS and vDB did not significantly change( P > 0.05) . Conclusion Estrogen can selectively increase the numbers of NOS-IR and Nestin-IR neurons in the different subregions of the basal forebrain, and this may be related to estrogen stimulation of the expressions of NOS and nestin.