Antinociceptive substances from Incarvillea delavayi

Antinociceptive activities of an Incarvillea delavayi extract, as well as i ts constituents, 8-epideoxyloganic acid and delavayine A, were evaluated in the acetic acid induced writhing test in mice. An oral administration of t he delavayi extract weakly decreased the number of writhings and stretching s in this test, in a dose-dependent manner. Furthermore, orally administere d 8-epideoxyloganic acid showed weak antinociceptive activity, whereas admi nistration by subcutaneous injection did not. However, subcutaneous injecti on of delavayine A, a novel monoterpene alkaloid, showed a more significant level of antinociceptive activity. (C) 2000 Elsevier Science Ltd. All righ ts reserved.