MORPHOLOGICAL AND HISTOLOGICAL STUDIES OF THE CHINESE DRUG LAO-GUAN-CAO

Lao-guan-cao has long been used in Chinese traditional medlcine.It is used as anantirheumatic and circulation promoting drug for the treatment of acute and chronic rheumatalgia;alsoused as a detoxicant for enteritis and bacillary dysentery.The dried aerial parts of Erodium stephanianumWilld.and Geranium wilfordii Maxim,(family Geraniaeeae)have been specified in the ChinesePharmacopoeia (1990 ed.)According to the literature and the authors’market investigations, the commercial drug Lao-guan-cao chiefly consists of the aerial parts of Erodium stephanianum Willd. Also those rather popularlyused in several provinces are the aerial parts of Geranium nepalense Sweet and G.sibiricum L. In this paper ,the morphological and histological characters of the crude drugs derived fromE. stephanianum Willd.,G.nepalense Sweet and G. sibiricum L. are described. It is found that the following characters are useful for distinguishing the drugs derived from theabove mentioned three species.(1) The shape and size of leaf;(2)the number and arrangement ofthe vascular bundles of stem;(3)the number of the vascular bundles in midrib and layers of palisadecells of leaf;(4)the presence or absence of stomata in upper epidermis;(5)the characters of cellscontaining crystals in sepal;(6)the characters of epidermis cells,cells containing crystals and fibersof pericarp;(7)the types of hairs and glandular hairs on epidermis of stem,leaf, sepal and pericarp;(8)the characters of anticlinal walls of epidermal cells of seed coat