Portable electrical stimulator for use in small animals

Abstract

The detailed electronic configuration of a lightweight (7 g) battery-operated portable electrical stimulator unit is described. It has proven useful for the study of the effects of chronic stimulation on skeletal muscle in small animals (i.e., the rat). The unit requires wavelengths in the infrared region for activation. This allows for remote triggering of the stimulator and permits it to function reliably even when animals are housed in rooms illuminated by fluorescent lamps. Unique to the system is the inclusion of a visual indicator of unit function (light-emitting diode), thus providing a convenient means of monitoring unit activation. The stimulator unit described has proven to be highly reliable and very useful for the study of alterations in gene expression in muscle subject to chronic use (M. Takahashi and D. A. Hood, J. Appl. Physiol. 74: 934–941, 1993).