Pharmacological studies on crude plant drugs, Shikon and Tooki (II) Shikonin and Acetylshikonin.

Abstract

Pharmacological effects of Shikonin and Acetylshikonin, pigment components of Shikon [Lithospermum officinale] were studied in mice, rats, guinea pigs and rabbits. The only difference between the chemical structures of the 2 pigments is that Acetylshikonin has the acetyl radical, while Shikonin does not. Though the activity was slightly different between the 2 compounds, the pharmacological effect of Shikonin was similar to that of Acetylshikonin. As the 2 pigments were extracted by ether from Shikon, systemic administration of these pigments showed the same effect as that of ether extract of Shikon as outlined in the 1st report. These compounds had no effect on blood coagulation, but inhibited the anticoagulant effect of heparin in rats. Topical application of both pigments (50 mg of 0.1% ointment) inhibited an increased vascular permeability and acute edema induced by histamine, anti-rat rabbit serum and heat. The activity was similar to that of 0.1% phenylbutazone ointment. These pigments increased proliferation of granuloma tissue in the cotton pellet method and promoted wound healing in rats. The results suggest that Shiunko, a main prescription of Shikon, is an effective ointment for cutaneous injuries.