紫背一點癀鎮痛抗炎作用及其有效成分之研究

Analgesic and Anti-Inflammatory Effects of Nervilia purpurea and Its Active Components

紫背一點癀(Nervilia purpurea)(HAYATA)(SCHLETHER)，係為蘭科植物，生產於臺灣中海拔陰濕的山區，依據文獻記載民間嘗用於抗炎、退癀及治療高血壓，但目前尚無其藥理研究報導。本研究室經初步篩選的試驗，發現紫背一點癀全草50%酒精／水抽出物，具有抑制小白鼠對醋酸所誘發的扭體反應。故依其形態將紫背一點癀分成葉及球莖兩部分，分別先以50%酒精水溶液加熱抽取，抽取液再用溶媒進行分配分離，各得乙酸乙酯層、正丁醇層及水溶等層。葉之乙酸乙酯層經柱層層析並經純化後得數個化合物，經進行藥理試驗，獲致結果如下：一、紫背一點癀全草粗抽出物對於ICR系雄性小鼠口服投與，劑量高達159/kg，仍未發現動物死亡的現象，其毒性顯現很低。二、紫背一點癀500mg/kg對小鼠熱板誘發之痛覺無明顯抑制作用。三、葉之乙酸乙酯層對小鼠以醋所誘發的扭體反應抑制作用較大。四、紫背一點癀於carrageenin及formalin等誘發大白鼠後足蹠浮腫試驗，具明顯有抑制作用。其抗發炎作用，以葉之水層最強。五、葉之乙酸乙酯層以大白鼠皮膚視窗法進行試驗，發現能抑制PGE2所誘發的滲透性增加作用。而且於對小鼠福馬林誘發的舔反應抑制作用較大。根據實驗結果，紫背一點癀之鎮痛抗炎作用，可能是藉由抑制PGE2等所產生的結果，其機理正進一步探討中。

Nervilia purpurea (H(subscript AYATA) S(subscript CHLETHER) (NP) (Orchidaceae), distributed in cool wet mountain areas of Taiwan, has been used as a folk medicine in Taiwan to treat the external injuries (such as bruises), weakness, pneumonia and hypertension. However, there arc few reports about its pharmacological effects. In our preliminary study, the crude extract of NP has been observed to inhibit the writhing response markedly in mice induced by acetic acid. Thus, we separated the herb into two portions. Each extract was separated with various solvents to produce six layers that included some compounds. We attempt to explore the pharmacological properties of those active compounds. Following results were obtained: (1) the median lethal dose (LD50) of NP crude extract was higher than 15gkg, orally. (2) the crude extracts of NP did not affect the nociceptive response in hot plate in mice. (3) substances in the ethyl acetate layer reduced acetic acid-induced writhing response. (4) the crude extract of NP could inhibit the inflammatory edema induced by carrageenin and formalin and the aqueous layer of leaf extract at most effective. (5) the ethyl acetate layer of leaf extract inhibited the skin permeability induced by PGE2 in the skin windows test and attenuated the licking response in formalin test. In conclusion, we suggest that NP possessed the analgesic and anti-inflammatory effects which may be related to the endogenous of prostaglandins.