Agonist activity at human CB2 receptor transfected in CHO cells assessed as inhibition of forskolin-stimulated adenylyl cyclase activity after 15 mins by liquid scintillation spectrophotometry
Agonist activity at CB1 receptor in mouse Neuro2a cells assessed as inhibition of forskolin-stimulated adenylyl cyclase activity after 15 mins by liquid scintillation spectrophotometry
Agonist activity at human CB2 receptor transfected in CHO cells assessed as inhibition of forskolin-stimulated adenylyl cyclase activity at 10 uM after 15 mins by liquid scintillation spectrophotometry
Agonist activity at CB1 receptor in mouse Neuro2a cells assessed as inhibition of forskolin-stimulated adenylyl cyclase activity at 10 uM after 15 mins by liquid scintillation spectrophotometry
Competition Receptor Binding Assay: Competition receptor binding was performed as previously described [Shoemaker et al., J. Pharmacol. Exp. Ther., 314:868-75]. Briefly, 50 μg of mouse brain homogenates were incubated for 90 minutes to attain equilibrium binding at room temperature with 0.2 nM [3H]CP-55,940, 5 mM MgCl2, and either increasing cannabinoid concentrations (0.1 nM to 10 μM), 10 μM WIN-55,212-2 (for non-specific binding) or vehicle (for total binding), in triplicate, in a volume of 1 mL of buffer containing 50 mM Tris, 0.05% bovine serum albumin (BSA) and 1% ethanol vehicle. Reactions were terminated by rapid vacuum filtration through Whatman GF/B glass fiber filters, followed by five washes with ice-cold buffer (50 mM Tris, 0.05% BSA). Filters were immediately placed into 7 mL scintillation vials to which 4 mL of ScintiVerse™ BD Cocktail scintillation fluid (Fisher Scientific, Fair Lawn, N.J.) was added. Bound radioactivity was determined after overnight incubation at room temperature and shaking, by liquid scintillation spectrophotometry with an efficiency of 44% (Tri Carb 2100 TR Liquid Scintillation Analyzer, Packard Instrument Company, Meriden, Conn.).
Competition Receptor Binding Assay: Competition receptor binding was performed as previously described [Shoemaker et al., J. Pharmacol. Exp. Ther., 314:868-75]. Briefly, 50 μg of mouse brain homogenates were incubated for 90 minutes to attain equilibrium binding at room temperature with 0.2 nM [3H]CP-55,940, 5 mM MgCl2, and either increasing cannabinoid concentrations (0.1 nM to 10 μM), 10 μM WIN-55,212-2 (for non-specific binding) or vehicle (for total binding), in triplicate, in a volume of 1 mL of buffer containing 50 mM Tris, 0.05% bovine serum albumin (BSA) and 1% ethanol vehicle. Reactions were terminated by rapid vacuum filtration through Whatman GF/B glass fiber filters, followed by five washes with ice-cold buffer (50 mM Tris, 0.05% BSA). Filters were immediately placed into 7 mL scintillation vials to which 4 mL of ScintiVerse™ BD Cocktail scintillation fluid (Fisher Scientific, Fair Lawn, N.J.) was added. Bound radioactivity was determined after overnight incubation at room temperature and shaking, by liquid scintillation spectrophotometry with an efficiency of 44% (Tri Carb 2100 TR Liquid Scintillation Analyzer, Packard Instrument Company, Meriden, Conn.).
Functional Assay: A functional assay screen for the inhibition of adenylate cyclase (AC) activity was chosen as the subsequent assay. This screen would allow us to gain a better understanding of the intrinsic activity of the analogues that displayed moderate to high sub-micromolar affinity for the CBRs. Reaching full-receptor occupancy, which is predicted to produce maximal efficacy, is desirable at 10 μM concentration of all the compounds was used. The non-selective CB1R/CB2R full agonist CP-55,940 was used as a positive control and it produced 45% AC-inhibition at CB1Rs endogenously expressed in Neuro2A cells (FIG. 19A) and 37% AC-inhibition in CHO cell transfected with hCB2 receptors (FIG. 19B). Most compounds tested exhibit AC-inhibition similar to that produced by the full agonist CP-55,940. TV-5-129, TV-6-249, and TV-6-41, however, produce lower AC-inhibition at CB1Rs than the full agonist CP-55,940 with −4, 18, and 16% inhibition, respectively (FIG. 19A). Despite little or no AC-inhibition observed at CB1Rs, these compounds behaved differently at CB2Rs. Specifically, the three compounds in question exhibited AC-inhibition that was in the range of the inhibition seen with CP-55,940 and were shown to inhibit adenylate cyclase with 22.1, 33.2, and 20.8%, respectively (FIG. 19B).
Functional Assay: A functional assay screen for the inhibition of adenylate cyclase (AC) activity was chosen as the subsequent assay. This screen would allow us to gain a better understanding of the intrinsic activity of the analogues that displayed moderate to high sub-micromolar affinity for the CBRs. Reaching full-receptor occupancy, which is predicted to produce maximal efficacy, is desirable at 10 μM concentration of all the compounds was used. The non-selective CB1R/CB2R full agonist CP-55,940 was used as a positive control and it produced 45% AC-inhibition at CB1Rs endogenously expressed in Neuro2A cells (FIG. 19A) and 37% AC-inhibition in CHO cell transfected with hCB2 receptors (FIG. 19B). Most compounds tested exhibit AC-inhibition similar to that produced by the full agonist CP-55,940. TV-5-129, TV-6-249, and TV-6-41, however, produce lower AC-inhibition at CB1Rs than the full agonist CP-55,940 with −4, 18, and 16% inhibition, respectively (FIG. 19A). Despite little or no AC-inhibition observed at CB1Rs, these compounds behaved differently at CB2Rs. Specifically, the three compounds in question exhibited AC-inhibition that was in the range of the inhibition seen with CP-55,940 and were shown to inhibit adenylate cyclase with 22.1, 33.2, and 20.8%, respectively (FIG. 19B).
Functional Assay: A functional assay screen for the inhibition of adenylate cyclase (AC) activity was chosen as the subsequent assay. This screen would allow us to gain a better understanding of the intrinsic activity of the analogues that displayed moderate to high sub-micromolar affinity for the CBRs. Reaching full-receptor occupancy, which is predicted to produce maximal efficacy, is desirable at 10 μM concentration of all the compounds was used. The non-selective CB1R/CB2R full agonist CP-55,940 was used as a positive control and it produced 45% AC-inhibition at CB1Rs endogenously expressed in Neuro2A cells (FIG. 19A) and 37% AC-inhibition in CHO cell transfected with hCB2 receptors (FIG. 19B). Most compounds tested exhibit AC-inhibition similar to that produced by the full agonist CP-55,940. TV-5-129, TV-6-249, and TV-6-41, however, produce lower AC-inhibition at CB1Rs than the full agonist CP-55,940 with −4, 18, and 16% inhibition, respectively (FIG. 19A). Despite little or no AC-inhibition observed at CB1Rs, these compounds behaved differently at CB2Rs. Specifically, the three compounds in question exhibited AC-inhibition that was in the range of the inhibition seen with CP-55,940 and were shown to inhibit adenylate cyclase with 22.1, 33.2, and 20.8%, respectively (FIG. 19B).