Fig. 5

Agonist activation of D2R reduces the size of clustered burst firing in AST-derived dopamine neurons or mouse dopamine neurons overexpressing α-synuclein. The experiments and analyses were performed in parallel and via a blinded experimental design. a₁ Representative recording of a spontaneously active AST-derived dopamine neuron before (aqua blue) and during (brown) application of quinpirole. a₂ Representative trace of a spontaneously active NAS-derived dopamine neurons shows a mixture of single spikes and burst activity. b₁ Representative recording of a spontaneously active mouse dopamine neuron overexpressing α-synuclein before (navy-blue) and during (wine) application of quinpirole. b₂ Representative trace of a spontaneously active wild type mouse dopamine neuron obtained from midbrain primary neuronal culture. c Phase-plane plot of action potentials generated from (a₁) and (a₂). d Phase-plane plot of action potentials generated from (b₁) and (b₂) e Interspike histogram (in ms) of human iPSCs-derived dopamine neurons for three conditions belonging, from top to bottom: AST-derived neurons at baseline (e₁), during quinpirole application (e₂) and NAS baseline (e₃). f Interspike histogram (in ms) of mouse midbrain dopamine neurons for three conditions belonging, from top to bottom: overexpressing α-synuclein at baseline (f₁), during quinpirole application (f₂) and WT baseline (f₃). n corresponds to the total number of spikes to determine the histogram