Fig. 6

Photo-stimulation of eNpHR3.0 at 488 nm enables efficient long-term hyperpolarization and inhibition. a Sample current-clamp measurements from a single cell (biased to about − 65 mV at rest) repetitively challenged with an inward current of constant amplitude either without (5 mW, left) or with photo-stimulation at 594 nm (5 mW, middle) or 488 nm (right), respectively. Note that yellow-light stimulation initially abolished action potential firing (#), which recovered during prolonged photo-stimulation periods. Also note that blue-light stimulation suppressed firing for the entire 1-min period on the background of a stable hyperpolarization. Insets: current responses to the last test pulse at higher temporal magnification (scale bars, 25 mV, 0.5 s). b Number of action potentials (AP) as a function of the test-pulse number. c Time-course of membrane potential (gray—period of photo-stimulation). Data are presented as mean ± SEM