Rutin was isolated from dried leaves and flowers of buckwheat (Fagopyrum esculentum
Moench.). The effects of rutin on angiotensin II-induced hypertrophy of cultured cardiac myocytes and
proliferation of cardiac fibroblasts of neonatal rats were evaluated by analyzing the cell surface area, measuring
the protein synthesis rate through 3H-leucine incorporation, and the MTT method. Rutin (0.8 to 8.0
mg/l) exhibited a strong inhibition on the hypertrophy and proliferation. The results suggested that rutin
from buckwheat flowers and leaves might have protective effects on cardiac hypertrophy.