SPLTRAK Abstract Submission
Investigating the Neuroendocrine and Behavioral Controls of Cannabis-Induced Feeding Behavior. 
Washington State University, Pullman, WA, United States
   Cannabis induces appetite, but little is known regarding its mechanistic control of feeding behavior. Previous studies have examined delta-9 tetrahydrocannabinol (THC), the primary psychoactive cannabinoid in cannabis, for its appetite-stimulating effects. However, few have investigated feeding following dry cannabis plant matter (CPM) exposure, the most widely consumed form of cannabis. Clinical data report that CPM-induced feeding only ensues after a time delay, suggesting additional signaling mechanisms beyond THC action. To address this, we utilized a novel vapor chamber system to administer CPM to rodents. Specifically ad libitum male Long Evans rats (n=8/group) were exposed to vaporized CPM and meal patterns were subsequently analyzed. Plasma levels of THC and the orexigenic hormone acyl-ghrelin (AG) were also quantified. Another cohort of 24hr deprived male rats (n=8/group) received CPM exposure following a 2hr re-feeding period prior to palatable ensure diet exposure. Additional rats were evaluated for CPM-induced feeding following pharmacologic blockade of AG secretion. Finally, experiments to measure motivated and anxiety-driven behavior following CPM exposure were performed. Results indicate that CPM exposure induced a delayed increase in meal frequency, an effect accompanied by elevated levels of plasma ghrelin and THC. CPM exposure also augmented ensure feeding in pre-fed rodents. CPM exposure did not alter motivated or anxiety-driven behavior. Importantly, blockade of AG secretion attenuated CPM-induced feeding. Collectively these data indicate that vaporized CPM stimulates feeding occurs in a time dependent manner and requires gastrointestinal release of AG.