Fatty acid binding proteins 5 and 7 differentially modulate phenotypic response to acute Δ9-tetrahydrocannabinol in female mice.

Fatty acid binding proteins (FABPs) are important regulatory proteins within the endocannabinoid system (ECS) which have also been implicated as carriers of Δ9-tetrahydrocannabinol (THC). The goal of this study was to further characterize how FABPs 5 and 7 interact with THC in vivo using transgenic knockout mice. Mice with or without FABP5 or FABP7 were administered a single 15 mg/kg dose of intraperitoneal injected THC and tested for locomotor activity, change in body temperature, and cataleptic response. Our results indicate that FABP5 deletion resulted in decreased locomotor activity, independent of THC administration, along with standard responses in the body temperature and catalepsy tests. FABP7 global deletion resulted in decreased locomotion in a genotype-dependent manner within the THC-treated groups, as well as genotype-dependent body temperature changes, but similar responses to the catalepsy test. Our findings implicate both FABP5 and FABP7 in the physiological responses to THC, in different manners, and further our understanding of how THC interacts with the ECS.