Figure 9.

Membrane potential changes in heart muscle in 3rd instar larvae for the halorhodopsin (eNpHR)-expressing line. (A1) When halorhodopsin is activated by yellow light, the heart stopped beating without the membrane hyperpolarizing. (A2) This preparation shows a sustained hyperpolarization during the yellow light pulse. (B) The changes in membrane potential from resting condition to peak response hyperpolarizing potentials during the light pulse are shown for each preparation. The circles overlaying on the trace indicate where the membrane potential is measured. Mean (± SEM) values are presented next to each distribution.