Tolerance and dependence to Δ9-tetrahydrocannabinol in rhesus monkeys: Activity assessments.

Cannabis withdrawal upon discontinuation of long-term, heavy Cannabis use is reported in humans; however, methods to establish the nature and intensity of cannabinoid withdrawal, especially directly observable signs, have not been widely established. This study quantified activity in the home cage o...

Full description

Bibliographic Details
Main Authors: Jenny L Wilkerson, David R Schulze, Lance R McMahon
Format: Article
Language:English
Published: Public Library of Science (PLoS) 2019-01-01
Series:PLoS ONE
Online Access:https://doi.org/10.1371/journal.pone.0209947
_version_ 1818924939340677120
author Jenny L Wilkerson
David R Schulze
Lance R McMahon
author_facet Jenny L Wilkerson
David R Schulze
Lance R McMahon
author_sort Jenny L Wilkerson
collection DOAJ
description Cannabis withdrawal upon discontinuation of long-term, heavy Cannabis use is reported in humans; however, methods to establish the nature and intensity of cannabinoid withdrawal, especially directly observable signs, have not been widely established. This study quantified activity in the home cage of rhesus monkeys and examined the extent to which activity can be used to quantify tolerance to and dependence on Δ9-tetrahydrocannabinol (Δ9-THC). Home-cage activity was measured in one group that received Δ9-THC (1 mg/kg s.c.) every 12 h (i.e., chronic Δ9-THC), and a second group that received Δ9-THC (0.1 mg/kg i.v.) once every 3 days (i.e., intermittent Δ9-THC). Treatment was temporarily discontinued in the chronic Δ9-THC group and the effects of rimonabant and Δ9-THC were examined in both groups. Activity counts were highest during the day (lights on 0600-2000 h) and were lower at night. Rimonabant (0.1-3.2 mg/kg i.v.) dose-dependently increased activity (maximum 20-fold) in the chronic Δ9-THC group but did not significantly alter activity in the intermittent Δ9-THC group. Δ9-THC (0.32-3.2 mg/kg i.v.) dose-dependently decreased activity counts (maximum 4-fold) in both groups but was somewhat more potent in the intermittent as compared with the Δ9-THC group. Discontinuation of Δ9-THC treatment resulted in an immediate (i.e., within 24 h) and time-related increase in activity. The time-related increase in home-cage activity upon abrupt discontinuation of chronic Δ9-THC treatment, as well as the effects of rimonabant to increase activity in monkeys receiving chronic, but not intermittent, Δ9-THC treatment, are consistent with signs of physical dependence on Δ9-THC in primates.
first_indexed 2024-12-20T02:33:18Z
format Article
id doaj.art-6caa7b57d0cd4673a7a9da443db22097
institution Directory Open Access Journal
issn 1932-6203
language English
last_indexed 2024-12-20T02:33:18Z
publishDate 2019-01-01
publisher Public Library of Science (PLoS)
record_format Article
series PLoS ONE
spelling doaj.art-6caa7b57d0cd4673a7a9da443db220972022-12-21T19:56:31ZengPublic Library of Science (PLoS)PLoS ONE1932-62032019-01-01143e020994710.1371/journal.pone.0209947Tolerance and dependence to Δ9-tetrahydrocannabinol in rhesus monkeys: Activity assessments.Jenny L WilkersonDavid R SchulzeLance R McMahonCannabis withdrawal upon discontinuation of long-term, heavy Cannabis use is reported in humans; however, methods to establish the nature and intensity of cannabinoid withdrawal, especially directly observable signs, have not been widely established. This study quantified activity in the home cage of rhesus monkeys and examined the extent to which activity can be used to quantify tolerance to and dependence on Δ9-tetrahydrocannabinol (Δ9-THC). Home-cage activity was measured in one group that received Δ9-THC (1 mg/kg s.c.) every 12 h (i.e., chronic Δ9-THC), and a second group that received Δ9-THC (0.1 mg/kg i.v.) once every 3 days (i.e., intermittent Δ9-THC). Treatment was temporarily discontinued in the chronic Δ9-THC group and the effects of rimonabant and Δ9-THC were examined in both groups. Activity counts were highest during the day (lights on 0600-2000 h) and were lower at night. Rimonabant (0.1-3.2 mg/kg i.v.) dose-dependently increased activity (maximum 20-fold) in the chronic Δ9-THC group but did not significantly alter activity in the intermittent Δ9-THC group. Δ9-THC (0.32-3.2 mg/kg i.v.) dose-dependently decreased activity counts (maximum 4-fold) in both groups but was somewhat more potent in the intermittent as compared with the Δ9-THC group. Discontinuation of Δ9-THC treatment resulted in an immediate (i.e., within 24 h) and time-related increase in activity. The time-related increase in home-cage activity upon abrupt discontinuation of chronic Δ9-THC treatment, as well as the effects of rimonabant to increase activity in monkeys receiving chronic, but not intermittent, Δ9-THC treatment, are consistent with signs of physical dependence on Δ9-THC in primates.https://doi.org/10.1371/journal.pone.0209947
spellingShingle Jenny L Wilkerson
David R Schulze
Lance R McMahon
Tolerance and dependence to Δ9-tetrahydrocannabinol in rhesus monkeys: Activity assessments.
PLoS ONE
title Tolerance and dependence to Δ9-tetrahydrocannabinol in rhesus monkeys: Activity assessments.
title_full Tolerance and dependence to Δ9-tetrahydrocannabinol in rhesus monkeys: Activity assessments.
title_fullStr Tolerance and dependence to Δ9-tetrahydrocannabinol in rhesus monkeys: Activity assessments.
title_full_unstemmed Tolerance and dependence to Δ9-tetrahydrocannabinol in rhesus monkeys: Activity assessments.
title_short Tolerance and dependence to Δ9-tetrahydrocannabinol in rhesus monkeys: Activity assessments.
title_sort tolerance and dependence to δ9 tetrahydrocannabinol in rhesus monkeys activity assessments
url https://doi.org/10.1371/journal.pone.0209947
work_keys_str_mv AT jennylwilkerson toleranceanddependencetod9tetrahydrocannabinolinrhesusmonkeysactivityassessments
AT davidrschulze toleranceanddependencetod9tetrahydrocannabinolinrhesusmonkeysactivityassessments
AT lancermcmahon toleranceanddependencetod9tetrahydrocannabinolinrhesusmonkeysactivityassessments