Reactions and rate constants of the dopamine activated pathway.

aunit in sec-1 bunit in sec-1 cunit in sec-1 dunit in nM-1sec-1 Da, Dopamine; D1R, Dopamine receptor; Gαβγ , Heterotrimeric G protein; GsαGTP, Active stimulatory Gsα subunit bound to guanosine triphosphate) ; GsαGDP, Inactive Gsα subunit bound to guanosine diphosphate; Gβγ , Dimeric G protein subunits dissociated from the α subunit of the trimeric G protein; CaMCa4, the complex of four calcium ions bound to calmodulin; AC1, adenylyl cyclase type 1; AC8, adenylyl cyclase type 8; PDE1, Phosphodiesterase type 1B; PDE1Cam, PDE1B bound with (and activated by) CaMCa4; PDE4, Phosphodiesterase type 4; PKAr, PKA regulatory subunit; PKAc, PKA catalytic subunit.