Molecular Psychiatry
October 2023
Briana J. Hempel, Madeline Crissman, Sruti Pari et al.
Peroxisome proliferator-activated receptors (PPARs) are a family of nuclear receptors that regulate gene expression. Δ9-tetrahydrocannabinol (Δ9-THC) is a PPARγ agonist and some endocannabinoids are natural activators of PPARα and PPARγ. However, little is known regarding their cellular distributions in the brain and functional roles in cannabinoid action. Here, we first used RNAscope in situ...
Journal of Neuroscience
January 18, 2023
Xiao Han, Ying Liang, Briana J. Hempel et al.
Cannabinoids modulate dopamine (DA) transmission and DA-related behavior, which has been thought to be mediated initially by activation of cannabinoid CB1 receptors (CB1Rs) on GABA neurons. However, there is no behavioral evidence supporting it. In contrast, here we report that CB1Rs are also expressed in a subset of DA neurons and functionally underlie cannabinoid action in male and female...
Addiction Biology
February 3, 2021
Bree A. Humburg, Chloe J. Jordan, Hai‐Ying Zhang et al.
30 citations
Abstract Despite extensive research, the rewarding effects of cannabinoids are still debated. Here, we used a newly established animal procedure called optogenetic intracranial self‐stimulation (ICSS) (oICSS) to re‐examine the abuse potential of cannabinoids in mice. A specific adeno‐associated viral vector carrying a channelrhodopsin gene was microinjected into the ventral tegmental area (VTA)...
Experimental and Clinical Psychopharmacology
April 2018
Briana J. Hempel, Matthew M Clasen, Katharine H Nelson et al.
Rising interest in medical marijuana has prompted research into its phytocannabinoid constituents, particularly Δ⁹-tetrahydrocannabinol (THC) and cannabidiol (CBD). Coadministration of CBD with THC has been shown to modulate a number of THC's effects, including its negative stimulus properties (e.g., anxiety, paranoia, psychosis) in a clinical setting. The present series of experiments extended...
Pharmacology, Biochemistry, and Behavior
May 2016
Briana J. Hempel, Alison Wakeford, Matthew M Clasen et al.
In pre-clinical models of marijuana abuse, there is relatively limited evidence of delta-9-tetrahydrocannabinol's (THC) rewarding effects, as indexed by its general inability to induce a place preference. One explanation for this failure is that its rewarding effects are masked by its concurrently occurring aversive properties. Consistent with this explanation, THC pre-exposure, which...
The FASEB Journal
April 1, 2016
Briana J. Hempel, Alison Wakeford, Matthew M Clasen et al.
Rationale Δ 9 ‐Tetrahydrocannabinol (THC) produces both aversive and rewarding effects in animal models. Given that the balance between a drug's affective properties is thought to underlie its abuse potential, it is important to consider these properties of THC and how they (and their balance) are impacted by various factors. In this context, previous studies have examined the effect of THC...