Abstract

Cannabidiol (CBD) and tetrahydrocannabinol (THC) have been studied for their influences of eating behaviors and food motivation. Research suggests CB­­­­­­₁ and CB₂ receptor interactions with these substances can stimulate overeating. CBD and WIN55,212-2, a CB₁ and CB₂ receptor agonist that produces similar effects to THC, were used to study motivation for self-administration of sucrose. Sprague-Dawley rats were trained with a variable ratio schedule starting at one sucrose administration every 45 seconds, doubling every day for three days. Rats were then randomly assigned into one of four treatment groups: WIN55,212-2 alone (1.2 mg/kg), CBD alone (10 mg/kg), the combination of WIN55,212-2 and CBD, or a saline control. Every day the number of presses to earn a reward would increase until the observed number of presses did not yield a single reward, this was described as the breakpoint. Each rat would receive a daily injection prior to one hour of free sucrose self-administration until the breakpoint was reached. Unexpectedly, the saline group was found to have the longest average time until breakpoint, and the WIN/CBD group was found to have the lowest average reinforcers per day. Although these findings do not support prior research, limitations in this specific study have a large impact on its results. Further research will be needed to determine the accuracy of these results, and if it is worthwhile to pursue solutions to appetite inhibiting cancer treatments like radiation and chemotherapy with these methods.