An implantable device electrically stimulates an organ of an animal in response to a trigger event. Between trigger event that device receives a wireless signal, such as a radio frequency signal, and stores energy from the signal in a plurality of capacitors. The capacitors are located within a electrical lead that extends to a stimulation electrode attached to the organ. That electrical lead has a hollow outer insulating tube with a pair of conductors extending longitudinally therein. The plurality of capacitors are connected between the pair of conductors. Thus the electrical lead serves as both a conductor of a stimulation current to the electrode and a housing for the plurality of capacitors.