Pharmacological studies on pueraria root. I. Fractional extraction of pueraria root and identification of its pharmacological effects.

Abstract

Pueraria root was extracted consecutively with acetone, methanol, and water, and 13 fractions (PA1-PA5, PM1-PM5, PW1-PW3) were prepared for basic pharmacological examinations. Many pharmacological actions were separated as fractionation of the extract progressed. Coexistence of substances having a mutually reverse pharmacological effect was found in the crude drug. Acute toxicity of each fraction was very weak. PA4, PA5, PM2, PW2, and PW3 decreased body temperature of mice, while PM4, PM5, and PW2 increased it. PA3, PA4, PA5, PM2, and PM4 exerted a papaverine-like action on the isolated guinea pig ileum, while PM1, PM3, and PM5 contracted this organ. PA5 and PM2 relaxed while PM3 contracted, the isolated guinea pig taenia coli. PA3, PA5, and PM2 showed a papaverine-like action on the isolated rat uterus. PA3, PA5, and all PM fractions contracted the isolated guinea pig vas deferens. PM2, PM3, and PG1 which was regarded as the component of PM2 potentiated the noradrenaline-induced contraction in this organ. PA3, PA5, all PM fractions, and PW2 inhibited electrically induced muscle contraction in the isolated frog sciatic nerve-sartorius muscle preparation. PA3, PA5, PM1, PM2, and PM4 contracted the isolated frog rectus abdominis muscle. PA3, PA5, PM1, PM3, PM4, PM5, and PW2 decreased blood pressure in anesthetized dogs, while PM2 elevated it. PA3, PA5, PM1, PM3, PM4, PM5, and PW2 increased femoral arterial blood flow in anesthetized dogs. Some discussions were made on the pharmacological actions of each fraction.