High resolution

Module 10: Figure medium spiny neuron signalling

Convergence of the signalling pathways activated in medium spiny neurons by dopamine and glutamate.

Medium spiny neurons have D1 dopamine receptors that act through the cyclic AMP signalling pathway, and N-methyl-D-aspartate (NMDA) receptors that activate Ca2+ entry and can induce the extracellular-signal-regulated kinase (ERK) pathway of the mitogen-activated protein kinase (MAPK) signalling system (Module 2: Figure ERK signalling). There is evidence of cross-talk between these two pathways that converge on dopamine and cyclic AMP-regulated phosphoprotein of apparent molecular mass 32 kDa (DARPP-32), which is a potent inhibitor of protein phosphatase (PP1). (See the text for further details.)