Behavioral Characterization of the Effects of Cannabis Smoke and Anandamide in Rats.
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 investigate...
| Main Authors: | , , , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Public Library of Science (PLoS)
2016-01-01
|
| Series: | PLoS ONE |
| Online Access: | http://europepmc.org/articles/PMC4827836?pdf=render |
| _version_ | 1818449421030916096 |
|---|---|
| author | Adriaan W Bruijnzeel Xiaoli Qi Lidia V Guzhva Shannon Wall Jie V Deng Mark S Gold Marcelo Febo Barry Setlow |
| author_facet | Adriaan W Bruijnzeel Xiaoli Qi Lidia V Guzhva Shannon Wall Jie V Deng Mark S Gold Marcelo Febo Barry Setlow |
| author_sort | Adriaan W Bruijnzeel |
| collection | DOAJ |
| description | 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 not prevented by rimonabant or pre-exposure to cannabis smoke. Serum Δ9-THC levels were 225 ng/ml after smoke exposure, which is similar to levels in humans after smoking cannabis. Exposure to cannabis smoke led to dependence as indicated by more rimonabant-precipitated somatic withdrawal signs in the cannabis smoke exposed rats than in the air-control rats. In conclusion, chronic cannabis smoke exposure in rats leads to clinically relevant Δ9-THC levels, dependence, and has a biphasic effect on locomotor activity. |
| first_indexed | 2024-12-14T20:35:08Z |
| format | Article |
| id | doaj.art-121d109b22d642a3a30ef6dcd63061d1 |
| institution | Directory Open Access Journal |
| issn | 1932-6203 |
| language | English |
| last_indexed | 2024-12-14T20:35:08Z |
| publishDate | 2016-01-01 |
| publisher | Public Library of Science (PLoS) |
| record_format | Article |
| series | PLoS ONE |
| spelling | doaj.art-121d109b22d642a3a30ef6dcd63061d12022-12-21T22:48:25ZengPublic Library of Science (PLoS)PLoS ONE1932-62032016-01-01114e015332710.1371/journal.pone.0153327Behavioral Characterization of the Effects of Cannabis Smoke and Anandamide in Rats.Adriaan W BruijnzeelXiaoli QiLidia V GuzhvaShannon WallJie V DengMark S GoldMarcelo FeboBarry SetlowCannabis 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 not prevented by rimonabant or pre-exposure to cannabis smoke. Serum Δ9-THC levels were 225 ng/ml after smoke exposure, which is similar to levels in humans after smoking cannabis. Exposure to cannabis smoke led to dependence as indicated by more rimonabant-precipitated somatic withdrawal signs in the cannabis smoke exposed rats than in the air-control rats. In conclusion, chronic cannabis smoke exposure in rats leads to clinically relevant Δ9-THC levels, dependence, and has a biphasic effect on locomotor activity.http://europepmc.org/articles/PMC4827836?pdf=render |
| spellingShingle | Adriaan W Bruijnzeel Xiaoli Qi Lidia V Guzhva Shannon Wall Jie V Deng Mark S Gold Marcelo Febo Barry Setlow Behavioral Characterization of the Effects of Cannabis Smoke and Anandamide in Rats. PLoS ONE |
| title | Behavioral Characterization of the Effects of Cannabis Smoke and Anandamide in Rats. |
| title_full | Behavioral Characterization of the Effects of Cannabis Smoke and Anandamide in Rats. |
| title_fullStr | Behavioral Characterization of the Effects of Cannabis Smoke and Anandamide in Rats. |
| title_full_unstemmed | Behavioral Characterization of the Effects of Cannabis Smoke and Anandamide in Rats. |
| title_short | Behavioral Characterization of the Effects of Cannabis Smoke and Anandamide in Rats. |
| title_sort | behavioral characterization of the effects of cannabis smoke and anandamide in rats |
| url | http://europepmc.org/articles/PMC4827836?pdf=render |
| work_keys_str_mv | AT adriaanwbruijnzeel behavioralcharacterizationoftheeffectsofcannabissmokeandanandamideinrats AT xiaoliqi behavioralcharacterizationoftheeffectsofcannabissmokeandanandamideinrats AT lidiavguzhva behavioralcharacterizationoftheeffectsofcannabissmokeandanandamideinrats AT shannonwall behavioralcharacterizationoftheeffectsofcannabissmokeandanandamideinrats AT jievdeng behavioralcharacterizationoftheeffectsofcannabissmokeandanandamideinrats AT marksgold behavioralcharacterizationoftheeffectsofcannabissmokeandanandamideinrats AT marcelofebo behavioralcharacterizationoftheeffectsofcannabissmokeandanandamideinrats AT barrysetlow behavioralcharacterizationoftheeffectsofcannabissmokeandanandamideinrats |