ABSTRACT
Antagonism by THC-ll-oic acid to one of the effects of THC in vitro has also been reported;3 the acid inhibits THC-induced synthesis of iPGE-(immunoreactive prostaglandin) (Cayman Chemical, personal communication) in WI-38 human lung fibroblasts, probably by inhibiting the action of COX (cyclooxygenase). Inhibition of prostaglandin (PG) synthesis is a typical property of NSAIDs (nonsteroidal anti-inflammatory drugs), and this observation3 suggests that THC-ll-oic acid may exhibit similar effects in experimental models of pain and inflammation. This possibility was tested
THC-II-0ic Acid
in several animal models in which it was observed that the acid behaved as an NSAID in the mouse hot plate test,5,10 the PAP (platelet-aggregating factor) and arachidonate-induced paw edema tests,6 the PPQ (paraphenylquinone) writhing assay,lO and PAP-induced mortality.6 These findings raised the possibility that the analgesic and anti-inflammatory properties ofTHC may, in fact, be due to its acid metabolites.
