SITES OF ANALGESIC ACTION OF 3,15-DIACETY LBENZOYLACONINE

In the rat hot plate test, vocalization induced by electric stimulatio n, tail flick test, and the mouse acetic acid writhing test, 3, 15-dia cetylhenzoylaconine (DABA) ip exhibited a dose-dependent analgesic act ivity. Intrathecally (ith) administered DABA (527, 1186 mu g kg(-1)) h ad no analgesic action. croinjection of DABA 35 - 75 mu g kg(-1) mu g, into the cerebral ventricle (icv) or the periaqueductal gray (FAG) ex erted a remarkable analgesic activity, which was abolished after bilat eral lesions of locus coeruleus (LC). Microinjection of DABA (20 mu g) into LC failed to produce apparent analgesic action. These results su ggested that the sites of analgesia of DABA were mainly at the central supraspinal structures, and FAG was one of the primary sites, while L C was one of the intermediate links.