Behavioral Characterization of the Effects of Cannabis Smoke and Anandamide in Rats

作者：Adriaan W. Bruijnzeel, Xiaoli Qi, Lidia Guzhva, Shannon Wall, Jie Deng, Mark S. Gold, Marcelo Febo, Barry Setlow · 发表于：PLoS ONE · 年份：2016 · DOI：10.1371/journal.pone.0153327 · 被引用次数：96 · 研究领域：Cannabis and Cannabinoid Research、Neurotransmitter Receptor Influence on Behavior、Neuroscience and Neuropharmacology Research

Cannabis is the most widely used illicit drug in the world. Delta-9-tetrahydrocannabinol (Δ9-THC) is the main psychoactive component of cannabis and its effects have been well-studied. However, cannabis contains many other cannabinoids that affect brain function. Therefore, these studies investigated the effect of cannabis smoke exposure on locomotor activity, rearing, anxiety-like behavior, and the development of dependence in rats. It was also investigated if cannabis smoke exposure leads to tolerance to the locomotor-suppressant effects of the endogenous cannabinoid anandamide. Cannabis smoke was generated by burning 5.7% Δ9-THC cannabis cigarettes in a smoking machine. The effect of cannabis smoke on the behavior of rats in a small and large open field and an elevated plus maze was evaluated. Cannabis smoke exposure induced a brief increase in locomotor activity followed by a prolonged decrease in locomotor activity and rearing in the 30-min small open field test. The cannabinoid receptor type 1 (CB1) receptor antagonist rimonabant increased locomotor activity and prevented the smoke-induced decrease in rearing. Smoke exposure also increased locomotor activity in the 5-min large open field test and the elevated plus maze test. The smoke exposed rats spent more time in the center zone of the large open field, which is indicative of a decrease in anxiety-like behavior. A high dose of anandamide decreased locomotor activity and rearing in the small open field and this was no...