Drug Testing and Analysis
April 2018
David Potter, Kathy Hammond, Shaun Tuffnell et al.
In 2005 and 2008, studies reported that cannabis in England had become dominated by the sinsemilla (unseeded female) form. The average potency (Δ9 -tetrahydrocannabinol [THC] content) of this material had doubled over the previous decade. Cannabis resin then circulating contained approximately equal ratios of THC and cannabidiol (CBD), whereas sinsemilla was almost devoid of CBD. Despite raised...
Neuropsychopharmacology
March 1, 2016
Elena H Chartoff, Shayla R Ebner, Angela Sparrow et al.
Negative affective states can increase the rewarding value of drugs of abuse and promote drug taking. Chronic cocaine exposure increases levels of the neuropeptide dynorphin, an endogenous ligand at kappa opioid receptors (KOR) that suppresses dopamine release in the nucleus accumbens (NAc) and elicits negative affective states upon drug withdrawal. However, there is evidence that the effects...
Biological Psychiatry
October 15, 2011
David Potter, Diane Damez-Werno, William A Carlezon et al.
Repeated exposure to drugs of abuse and stress increase dynorphin, a κ opioid receptor (KOR) ligand, in the nucleus accumbens (NAc). Acute KOR activation produces dysphoria that might contribute to addictive behavior. How repeated KOR activation modulates reward circuitry is not understood. We used intracranial self-stimulation (ICSS), a method that provides a behavioral index of reward...
Neuropsychopharmacology
October 2008
Elena H Chartoff, David Potter, Diane Damez-Werno et al.
Stress and chronic exposure to drugs of abuse can trigger addictive and depressive disorders. Both stimuli increase activity of dynorphin, a neuropeptide that acts at kappa-opioid receptors (KORs). In humans, KOR agonists cause dysphoria, raising the possibility that dynorphin modulates the depressive-like effects of stress and chronic drug use. We examined if KOR activation alters sensitivity...
Journal of Pharmacology and Experimental Therapeutics
January 2008
Cécile Béguin, David Potter, Jennifer A DiNieri et al.
Several preclinical studies indicate that selective kappa-opioid receptor (KOR) antagonists have antidepressant-like effects, whereas KOR agonists have opposite effects, suggesting that each might be useful in the treatment of mood abnormalities. Salvinorin A (salvA) is a valuable KOR agonist for further study due to its high potency and receptor selectivity. However, it has short lasting...