[Study of stinging crystals in tian nanxing].
OBJECTIVE
To test whether the raphides in Tian Nanxing (Pinellia pedatisecta Schott) caused irritation.


METHODS
Scan Electron Microscope and Microscope Oberservation; Animal experimental study.


RESULTS
Through the comparision of unprocessed Tian Nanxing to processed ones which included 36 h, 72 h, 120 h processed samples, the great modifications in the structure of raphides, especially for the ones with barbs in the processed samples was observed with time course study. A further animal experimental study went to show that the rate of change for raphides with barbs existed a dose-reponse relationship to irritation.


CONCLUSIONS
Investigations of the causes of these reactions showed that raphides of calcium oxalate are, at least in part, responsible for the Tian Nanxing's irritation.
He
Yan
Y
Inst of Chinese Materia Medica, China Academy of Tradional Chinese Medicine, 100700 Beijing, China.
Feng
Xue-feng
XF
Sun
Jie
J
D019342:Acetic Acid; D000534:Alum Compounds; D000818:Animals; D002129:Calcium Oxalate / Q000737:chemistry / Q000302:isolation & purification / Q000633:toxicity; D003229:Conjunctival Diseases / Q000139:chemically induced*; D003460:Crystallization; D004305:Dose-Response Relationship, Drug; D004487:Edema / Q000139:chemically induced*; D006358:Hot Temperature; D030021:Pinellia / Q000737:chemistry*; D010946:Plants, Medicinal / Q000737:chemistry*; D011817:Rabbits; D027343:Rhizome / Q000737:chemistry; D013678:Technology, Pharmaceutical / Q000379:methods
D000534:Alum Compounds; D002129:Calcium Oxalate; C041524:aluminum sulfate; D019342:Acetic Acid