ANP suppressed IRK+, but SNAP had no effect.A, A 5 min application of ANP (50 nm) produced an ∼70% suppression of IRK+that recovered 22 min after removal. The trace labeled ANP was recorded 2 min after removal of ANP. B, Freshly mixed SNAP was perfused at a concentration of 1 mm. No effect on IRK+ was observed. In both examples, the control trace was recorded before agonist application, and the test traces were recorded after agonist removal. All traces are averages of four successive ramps.