甘草及其成分對Carrageenan誘發大白鼠後腳掌水腫的作用

Effects of Licorice and Its Active Principles on Carrageenan-Induced Edema of the Rat Hind-Paw

甘草是一種最常見的中藥材，而甘草具有消炎作用的主成分是甘草酸和甘草次酸。已有報導對棉球引致肉芽腫增生(cotton pledget induced granulation)、甲醛誘發的腳掌腫(formaldehyde induced paw swelling)、角叉菜誘發的腳掌腫(carrageenan induced paw swelling)都可被甘草次酸抑制。本實驗以carrageenan來誘發大白鼠後腳掌水腫，以測試甘草水抽提液、甘草酸和甘草次酸的抗發炎作用。測試藥物是在以注射0.1ml之1% lambda carrageenan到大白鼠後腳掌前l小時口服給與。結果顯示，正對照藥物indomethacin(5mg/kg)可完全抑制carrageenan給後1-6小時所產生的水腫，而甘草次酸(200mg/kg)只有部分抑制作用。給與100，200和500mg/kg的甘草酸，以及合相當於甘草酸劑量的甘草水抽提液，對水腫的產生則沒有影響。給與500mg/kg甘草次酸的作用和給與200mg/kg的結果相反，對於carrageenan誘導的水腫反而有促進及加強的作用。上述結果顯示甘草次酸對抗carrageenan誘導水腫產生的抗發炎活性很窄。

The anti-inflammatory effects of the aqueous extract of licorice (Glycyrrhizae Radix, GR), glycyrrhizin (GL). and 18β-glycyrrhetinic acid (GA) on carrageenan-induced edema of the rat hind-paw were compared. Tested drugs were administered orally 1 hr prior to the subplantar injection of 0.1 m1 mixture of 1 % lambda carrageenan into the right hind-paw of the rat. The edema formation during 1-6 hr was completely blocked by 5 mg/kg indomethacin (as a positive control) and was partially attenuated by 200 mg/kg GA. Both GL and GR, at the doses containing equivalent quantities of 100, 200, and 500 mg/kg of GL, had little effects on edema formation. In contrast to 200 mg/kg GA, 500 mg/kg GA facilitated and increased the carrageenan-induced edema formation. This result indicates that GA has very narrow margin of anti-inflammatory activity on carrageenan induced edema.