A PHOSPHORYLATION CASCADE IN THE BASAL-GANGLIA OF THE MAMMALIAN BRAIN- REGULATION BY THE D-1-DOPAMINE-RECEPTOR - A MATHEMATICAL-MODEL OF KNOWN BIOCHEMICAL REACTIONS

Stimulation of the dopamine D-l receptor in the corpus striatum initia tes a cascade of biochemical events. These events include: activation of adenylate cyclase, stimulation of cAMP-dependent protein kinase, pr otein phosphorylation and inhibition of phosphoprotein phosphotase-1. This article presents and discusses a mathematical model of these bioc hemical events (and their dependence upon the concentration of cytosol ic calcium). According to this model, the activity of calcineurin (whi ch is regulated by the concentration of cytosolic calcium ions) counte rbalances the activity of the ''D-1 cascade'' The combined activity of the ''D-1 cascade'' and calcineurin can regulate the activity of calc ium- and calmodulin-dependent protein kinase II.