6种不同基源钩藤药材的显微鉴别

Microscopic Identification of Uncaria Medicinal Material from Six Different Species

目的：研究6种不同基源钩藤药材的显微特征,对钩藤药材进行分种鉴别。方法：研究光镜下6种钩藤属植物的茎、钩、叶横切面特征和粉末显微特征。结果：不同种的钩藤在组织构造方面有基本相同之处,由外到内均由表皮、皮层、韧皮部、木质部及髓部组成。大多数钩藤的皮层、韧皮部及髓部薄壁细胞中均含棕色内含物。但各种之间又有不同特征,如主脉在叶的腹背面突出的形状、栅栏组织的列数、维管束的个数以及薄壁细胞中可见的草酸钙晶体类型。6种钩藤药材的显微特征比较研究表明,茎的横切面观轮廓、表皮毛的有无、韧皮部与木质部比例、形成层是否明显成环、射线宽窄和导管散在或径向相连以及髓部所占比例;叶主脉在叶的腹、背面凸出的形状、栅栏组织的列数和薄壁细胞中所含晶体种类;钩的形状等可作为钩藤属分种鉴别依据。粉末鉴定主要依据表皮细胞的形状、表皮细胞内是否存在油滴状物以及有无梯纹、环纹和网纹导管加以区别。结论：以上特征可以作为不同基源钩藤药材鉴别依据。

Objective： To study the microscopic characteristics of Uncaria medicinal material from six different species, and provide basis for fundamental identification of Uncaria medicinal material. Method：Transection characteristics and powder microscopic characteristics of stem,hook and leaf from 6 species of Uncaria were observed under electron microscope. Result： The tissues and structures of different species of Uncaria were basically the same composed of epidermis,cortex,phloem,xylem and medulla from outside to inside. Most of the cortex,phloem and pith parenchyma cells of Uncaria contained brown inclusion,but there were different features in different species,such as the shape of main veins on the back of abdomen, the number of columns of the palisade tissue,the number of vascular bundles,and the type of crystal of calcium oxalate visible in parenchyma cells. The comparative microscopic characteristics of six species of Uncaria medicinal material showed that characters such as the transverse section profile of stem,the presence or absence of epidermal hair,the proportion of phloem and xylem,the presence of clear ring in cambium,the width of radiation ray,the scattered or radially connected catheters,the proportion of pith as well as the protruding shape of main veins（ of leaves） in ventral and dorsal surface,the column number of palisade tissue,the type of crystals in parenchyma cells and the shape of hook,were used as the fundamental identification characteristics among various species. Powder identification included the shape of epidermal cells and the presence of oil droplets,ladder vessel and reticulate vessel within those cells. Conclusion： The above characteristics can be used as the identification basis for the six species of Uncaria medicinal material.