CNR1 and Obesity: In addition, nodifferences were present in D1 and D2 but in COMT in rats exposed to HFD; this differencewas located in obesity-prone (OP) rats.27 One part of the mesolimbic circuit is the nucleus accumbens (Nacb).The Nacb shell motivates consumption of dietary fat in rats, and whenD1Rs are inhibited in the lateral shell, a reduction in fat consumptioncan be seen.32 The endocannabinoid systemis formed by CB1 and CB2 receptors.