Ro 67-7476 is a positive allosteric modulator of metabotropic glutamate receptor 1 (mGluR1) that enhances glutamate-induced calcium release in HEK293 cells expressing rat mGluR1a (EC50 = 1.74 μM). It is selective for rat mGluR1 over rat mGluR2, mGluR4, and mGluR8 at a concentration of 10 μM. Ro 67-7476 increases the amplitude of mGluR1 excitatory postsynaptic potentials (EPSCs) evoked by 2,3-dihydroxy-6-nitro-7-sulfamoylbenzoquionxaline, picrotoxin, or AP5 in the Purkinje cells of rat cerebellar slices. It activates ERK1/2 phosphorylation in the absence of exogenously added glutamate (EC50 = 163.3 nM).
