2, 3, 4, 5-Tetrahydro-7, 8-dihydroxy-1-phenyl-1H-3-benzazepine, Animals, Chromans, Dopamine and cAMP-Regulated Phosphoprotein 32, Dyskinesia, Drug-Induced, Mice, Mice, Congenic, Mice, Inbred C57BL, Mice, Knockout, Receptors, Dopamine D4, Receptors, Dopamine D5, Signal Transduction
The role of D(1)-like [D(1), D(5)] and D(2)-like [D(2), D(3), D(4)] dopamine receptors and dopamine transduction via DARPP-32 in topographies of orofacial movement was assessed in restrained mice with congenic D(4) vs. D(5) receptor vs. DARPP-32 'knockout'. D(4) and DARPP-32 mutants evidenced no material phenotype; also, there were no alterations in topographical responsivity to either the selective D(2)-like agonist RU 24213 or the selective D(1)-like agonist SK and F 83959. In contrast, D(5) mutants evidenced an increase in spontaneous vertical jaw movements, which habituated more slowly than in wildtypes, and a decrease in horizontal jaw movements; topographical responsivity to SK and F 83959 and RU 24213 was unaltered. D(5) receptors regulate distinct topographies of vertical and horizontal jaw movement in an opposite manner. In assuming that the well-recognised role of the D(1)-like family in regulating orofacial movements involves primarily D(1) receptors, a role for their D(5) counterparts may have been overlooked.
Tomiyama K, Makihara Y, Yamamoto H, O'Sullivan G, Nally RE, Tighe O, Kinsella A, Fienberg AA, Grandy DK, Sibley DR, Croke DT, Koshikawa N, Waddington JL. Disruption of orofacial movement topographies in congenic mutants with dopamine D5 but not D4 receptor or DARPP-32 transduction 'knockout'. European Neuropsychopharmacology 2006;16(6):437-45.