Regional and temporal expression of sodium channel messenger RNAs in the rat brain during development

Summary The distribution of mRNA expression for three types of voltage gated neuronal sodium-channels was studied in the rat brain at different developmental stages (embryonal day E18, postnatal day P5 and adult). With the in-situ hybridization technique, using synthetic DNA-oligomer probes, pronounced regional and temporal variations in the expression levels of the different channel subtypes could be detected. In comparison with types I and III, sodium channel II mRNA was the most abundant subtype at all developmental stages. Maximal expression of sodium channel II mRNA was seen at P5 in virtually all parts of the grey matter, except for the cerebellum. In adult rat brain in contrast, sodium channel II mRNA levels were maximal in the granular layer of the cerebellum, whereas in all other regions expression had decreased to roughly 50% of postnatal levels. Na channel I expression was virtually absent at E18 and showed highest levels at P5, with maxima in the caudate nucleus and hippocampus. In the adult brain, expression of Na-channel I was nearly absent in the neocortex, but well detectable in the cerebellum and, at lower levels in the striatum and thalamus. Sodium channel III was mainly expressed at the embryonal stage and showed a decrease to very low levels with little regional preferences in the adult.Supported by Deutsche Forschungsgemeinschaft grant no.: Cr 30/16     

去卵巢大鼠骨质疏松病理学观察及NOS荧光素原位杂交研究

目的观察去卵巢大鼠骨质疏松病理形态和计量学改变以及NO与骨代谢的关系,探讨NO在骨质疏松发病机制中的作用和意义。方法通过图像分析仪对骨组织进行形态计量学分析及荧光素原位杂交方法观察eNOS在成骨细胞和破骨细胞中的表达。结果在去势模型组相对骨小梁体积、骨小梁平均厚度及eNOS在成骨细胞与破骨细胞中的表达较假手术组减少(<0.05),尼尔雌醇/左炔诺孕酮治疗组相对骨小梁体积、骨小梁平均厚度及成骨细胞与破骨细胞内eNOS的表达均较去势模型组明显升高(<0.01)。结论去势后雌性大鼠骨丢失为骨转换加快和重建负平衡(骨吸收超过骨形成)所致;成骨细胞与破骨细胞代谢与NOS表达有关,破骨细胞功能与NO呈负相关关系。尼尔雌醇和左炔诺孕酮能降低这种骨转换的负平衡并且提高成骨细胞与破骨细胞内NO水平,从而影响其功能,达到抑制骨吸收,降低骨转换的目的。