- Mutational analysis and molecular modeling of the binding pocket of the metabotropic glutamate 5 receptor negative modulator 2-methyl-6-(phenylethynyl)-pyridine. Malherbe, P., Kratochwil, N., Zenner, M.T., Piussi, J., Diener, C., Kratzeisen, C., Fischer, C., Porter, R.H. Mol. Pharmacol. (2003)