STUDIES ON THE HYPOTENSIVE EFFECT OF HUANG-CHIN

Huang-chin, the root of Scutellaria baicalensis Georgi., family labiatae, is used in Chinese medicine as an analgesic and antipyretic. Its value as a hypotensive drug has been recently reported. The present work was conducted to study its hypotensive and some related effects. In anesthetized dogs, the infusion of the herb produced a prompt and marked fall of blood pressure when injected intravenously(0.1g/kg), and a gradual fall of 10-30mm Hg within 2 hours in the majority of dogs when given by stomach tube(1g/kg). The yellow crystalline powder, extracted with ethyl alcohol from the drug, also exhibited a high potency of hypotensive action in a intramuscular dose of 0.02g/kg, indicating that it might be the active principle of the crude drug. The samples obtained from different sources varied in their hypotensive potencies. The drug showed a slight vasodilating effect in perfusion experiments on frog's lower limbs and rabbit's ears, and a mild sedative effect in rabbits and mice. Both of these effects might play a part in the hypotensive action.