A major metabolite of Δ1-tetrahydrocannabinol reduces its cataleptic effect in mice

Abstract
The results described here demonstrate that THC-induced catalepsy in mice can be substantially inhibited by the prior administration of Δ1-THC-7-oic acid, the major metabolite of THC in most species including humans. This raises the possibility that the intensity and duration of action of THC may depend to a large degree on the levels of this metabolite at the sites of action.