Figure 1

Cannabis Vapor Chamber Design, Feeding Dose Response, and Enhanced Hedonic Feeding. (A) Vaporized cannabis was delivered to a positive ventilated rat chamber (Allentown, box dimensions 14 in x 10 in x 7 in; lid dimensions 14 in x 10 in x 2.5 in) via plastic tubing affixed to the VapirRise 2.0 (Vapir, CA) with a plastic 3D-printed union and the cage with a custom designed port. A fan on the vaporizer drives aerosolized cannabis into the chamber during testing at a flow rate of less than 1 L/min. Vaporized cannabis is exhausted with a house vacuum system and chambers were thoroughly cleaned with 70% ethanol between sessions. A plastic stopcock controls the flux of air into and out of the chamber. (B) A one-way ANOVA indicated that free-feeding rats receiving 800 mg of cannabis vapor displayed increased feeding behavior (F_1,14 = 12.6511, p = 0.0032). In contrast, food intake in rats that received 200 or 400 mg of cannabis vapor did not differ significantly from air-exposed controls. (C) 2 hr re-feeding on chow prior to air or cannabis exposure did not differ between groups. (D) Following behavioral satiation, cannabis exposure led to significantly increased cumulative consumption of Ensure indicating that this manipulation augmented hedonic feeding behavior. Ensure intake in cannabis exposed rats was significantly different from air-exposed rats at 120 min (F_1;14 = 4.642, p = 0.0491), 150 min (F_1;14 = 8.0542, p = 0.0132), and 180 min (F_1;14 = 5.6319, p = 0.0325). There were no significant differences in Ensure intake before or after these time points.