牦牛和柴达木黄牛颈动脉体的组织微细结构比较

目的比较牦牛和柴达木黄牛颈动脉体(CB)的组织微细结构特征。方法选择健康成年牦牛和柴达木黄牛各5头,采用组织学染色、免疫组织化学SP法和透射电子显微镜技术,观察CB的显微及超微结构特征,并运用显微体视学方法比较两种动物CB中Ⅰ型细胞(明细胞、暗细胞)、Ⅱ型细胞和血管的体积密度(Vv)、面密度(Sv)、比表面(δ)、面数密度(NA)。结果牦牛和柴达木黄牛CB均由实质和间质构成,实质由大量的圆形或椭圆形的小球密集组合而成,小球内有丰富的实质细胞。牦牛Ⅰ型细胞数量多于柴达木黄牛,但其胞质内含的线粒体和特有的电子致密核心囊泡(EDCV)相对小而多。柴达木黄牛小球之间的结缔组织及内含的间质细胞明显多于牦牛,而牦牛CB中血管数量多于柴达木黄牛,而且管腔较大。牦牛CB明细胞的Vv、Sv、NA显著大于柴达木黄牛(P0.01);牦牛δ小于柴达木黄牛(P0.05)。牦牛暗细胞的Vv、Sv显著小于柴达木黄牛(P0.05),两组中NA和δ差异不显著(P0.05)。两种动物CB中Ⅱ型细胞的Vv、Sv、NA、δ差异均不显著(P0.05)。牦牛微血管的Vv、Sv、NA显著大于柴达木黄牛(P0.01),而δ显著小于柴达木黄牛(P0.01)。结论牦牛CB形成了固有的组织细胞成分和血管网形态特征以增强对高原低氧环境的适应能力。

Comparison of microstructures of the carotid body between yaks and chaidamu yellow cattles

Objective To compare the structural characteristics of the carotid body （CB） between yaks and chaidamu yellow cattles. Methods Health adult yaks (n=5) and chaidamu yellow cattles (n =5) were used in this study. The microstructure and ultrastructure of CB were observed by histologial, immunohistochemical SP methods and transmission electron microscopy techniques. The volume density(Vv), surface density(Sv), numerical density on area(NA) and specific surface(δ) of type Ⅰ cells(light and dark) and type Ⅱ cells and microvessels of carotid body were compared by light microscopy and microstereology between yaks and chaidamu yellow cattles. Results The CBs of yak and chaidamu yellow cattle were composed of parenchyma and mesenchyme. There were many round or oval gloubs with rich parenchymal cells. There were more type Ⅰ cells in yaks than in chaidamu yellow cattles, but there were less and smaller mitochondria and electron dense cored vesicles(EDCV) of the type I cells in yaks than in chaidamu yellow cattles. The connective tissue among gloubs and interstitial cells in chaidamu yellow cattles were significantly more than yaks, but there were more rich capillaries in mesenchyme and bigger vascular lumen in yaks than in chaidamu yellow cattles. The Vv、Sv、NAof CB light cells in yaks were significantly greater than that in chaidamu yellow cattles (P<0.01),while δ of CB light cells in yaks was less than in chaidamu yellow cattles(P>0.05). The Vv、Sv of CB dark cells in yaks were significantly less than in chaidamu yellow cattles (P<0.05), and there was no significant difference of NAand δ between yaks and chaidamu yellow cattles(P>0.05). In type Ⅱ cells, there was no significant difference in Vv、Sv、NA、δ between two groups (P>0.05). The Vv、Sv、NA of the CB microvessels in yaks were obviously greater than that in chaidamu yellow cattles (P<0.01), while δ in yaks CB was significantly less than in chaidamu yellow cattle (P<0.01). Conclusion The inheret tissue cell composition and vascular net of yak CB are formed to enhance the adaptability to plateau hypoxic environment.