Fig. 3.

AA and PLA₂ induce a current with similar I–V characteristics as the current induced by dopamine, both in standard and high extracellular [K⁺]_o. A,I–V relationships of the current induced by AA (50 μm), PLA₂ (50–122.5 U/ml), or dopamine (1 μm) were determined with the use of linear voltage ramp protocols (34 mV/sec) as described in Materials and Methods.Left panels, Standard extracellular potassium (1.7 mm; n = 3, n = 4,n = 7 for AA, PLA₂, and dopamine, respectively). Right panels, High extracellular potassium (20 mm; n = 2,n = 4, n = 2 for AA, PLA₂, and dopamine, respectively). B, Curves from A were normalized with respect to the current at −40 mV (1.7 mm K⁺) or to the peak inward current amplitude (20 mmK⁺).