CTEP (RO4956371)

Radioligand Binding Assays

For all filtration radioligand binding assays, membrane preparations expressing the target receptors or receptor combinations are resuspended in radioligand binding buffer (15 mM Tris-HCl, 120 mM NaCl, 5 mM KCl, 1.25 mM CaCl2, and 1.25 mM MgCl2, pH 7.4), and the membrane suspension is mixed with the appropriate concentrations of radioligand and nonlabeled drugs in 96-well plates in a total volume of 200 μL and incubated for 60 min at the appropriate temperature. At the end of the incubation, membranes are filtered onto Whatman Unifilter preincubated with 0.1% polyethyleneimine in wash buffer (50 mM Tris-HCl, pH 7.4) with a Filtermate 196 harvester and washed three times with ice-cold wash buffer. Radioactivity captured on the filter is quantified on a Topcount microplate scintillation counter with quenching correction after the addition of 45 μL of MicroScint 40 per well and shaking for 20 min. The concentration of membranes and incubation time is determined for each assay in pilot experiments.

Animal models

Adult male C57BL/6 mice model; Adult male Sprague-Dawley rats model; Fmr1 knockout mouse model

Dosage form

0.01 to 3.0 mg/kg; oral gavage; for 18 hours; or 2 mg/kg per 48 hr p.o. for 2 weeks

Applications

CTEP (0.1 and 0.3 mg/kg) was dose-dependently active in the stress-induced hyperthermia procedure in mice and the Vogel conflict drinking test in rats [1]. Moreover, CTEP corrected excessive protein synthesis, mGlu-long-term depression, and audiogenic seizures in the Hippocampus of Fmr1 knockout mice [2].

Other notes

Please test the solubility of all compounds indoor, and the actual solubility may slightly differ with the theoretical value. This is caused by an experimental system error and it is normal.

References:

1. Lindemann, L., Jaeschke, G., Michalon, A., Vieira, E., Honer, M., Spooren, W., Porter, R., Hartung, T., Kolczewski, S., Buttelmann, B., Flament, C., Diener, C., Fischer, C., Gatti, S., Prinssen, E. P., Parrott, N., Hoffmann, G. and Wettstein, J. G. (2011) CTEP: a novel, potent, long-acting, and orally bioavailable metabotropic glutamate receptor 5 inhibitor. J Pharmacol Exp Ther. 339, 474-486

2. Michalon, A., Sidorov, M., Ballard, T. M., Ozmen, L., Spooren, W., Wettstein, J. G., Jaeschke, G., Bear, M. F. and Lindemann, L. (2012) Chronic pharmacological mGlu5 inhibition corrects fragile X in adult mice. Neuron. 74, 49-56