PT  - JOURNAL ARTICLE
AU  - T. W. Grim
AU  - A. J. Morales
AU  - B. F. Thomas
AU  - J. L. Wiley
AU  - G. W. Endres
AU  - S. S. Negus
AU  - A. H. Lichtman
TI  - Apparent CB<sub>1</sub> Receptor Rimonabant Affinity Estimates: Combination with THC and Synthetic Cannabinoids in the Mouse In Vivo Triad Model
AID  - 10.1124/jpet.117.240192
DP  - 2017 Jul 01
TA  - Journal of Pharmacology and Experimental Therapeutics
PG  - 210--218
VI  - 362
IP  - 1
4099  - http://jpet.aspetjournals.org/content/362/1/210.short
4100  - http://jpet.aspetjournals.org/content/362/1/210.full
SO  - J Pharmacol Exp Ther2017 Jul 01; 362
AB  - Synthetic cannabinoids (SCs) represent an emerging class of abused drugs associated with psychiatric complications and other substantial health risks. These ligands are largely sold over the internet for human consumption, presumably because of their high cannabinoid 1 receptor (CB1R) affinity and their potency in eliciting pharmacological effects similar to Δ9-tetrahydrocannabinol (THC), as well as circumventing laws illegalizing this plant. Factors potentially contributing to the increased prevalence of SC abuse and related hospitalizations, such as increased CB1R efficacy and non-CB1R targets, highlight the need for quantitative pharmacological analyses to determine receptor mediation of the pharmacological effects of cannabinoids. Accordingly, the present study used pA2 and pKB analyses for quantitative determination of CB1R mediation in which we utilized the CB1R-selective inverse agonist/antagonist rimonabant to elicit rightward shifts in the dose-response curves of five SCs (i.e., A-834,735D; WIN55,212-2; CP55,950; JWH-073; and CP47,497) and THC in producing common cannabimimetic effects (i.e., catalepsy, antinociception, and hypothermia). The results revealed overall similarity of pA2 and pKB values for these compounds and suggest that CB1Rs, and not other pharmacological targets, largely mediated the central pharmacological effects of SCs. More generally, affinity estimation offers a powerful pharmacological approach to assess potential receptor heterogeneity subserving in vivo pharmacological effects of SCs.