Two telestimulation systems for chronic indirect muscle stimulation in caged rabbits and mice

Telestimulation systems are described for chronic indirect muscle stimulation in caged rabbits and mice. Both systems use a 5 MHz carrier frequency transmission and consist of a transmitter and a receiver. The latter is fixed to the back of the animal. The system for rabbits uses pulse width modulation for transmitting stimulation frequency and amplitude. Duration of the stimulation impulse is generated in the receiver. Clock batteries in the receiver generate impulse energy. The impulse amplitude varies by only 1%. In the system used for mice, impulse energy is transmitted together with the stimulation frequency. This is achieved by a receiver containing two separate coils which are opposed to each other in an angle of 80 degrees C. In contrast to the rabbit system, the duration of the stimulation impulse is generated by the impulse width of the 5 MHz carrier. The amplitude of the stimulation impulse depends on the amplitude of the carrier. Due to the geometry of induction coil and receiver, impulse intensity varies at maximum by only 10%.