In vivo extracellular recording of sympathetic ganglion activity in a chronic animal model.

Surgery of the sympathetic system is performed for a variety of indications, hyperhidrosis being a major one. Despite excellent results, sympathectomy for hyperhidrosis bears a number of sequels, some of which may be devastating. Several surgical methods, empirically advocated to alleviate these problems, have only limited success. Chronic in vivo recording of the electrical activity from sympathetic ganglia may assist in understanding and clarifying complex problems of sympathetic surgery; however, no suitable method has been reported. An electrode device developed by our group was implanted on the stellate ganglion, in a chronic animal model (dog). The signals obtained were amplified, filtered, and transmitted via an A/D interface to be acquired and saved on a computer, using special software which we developed. Our method enabled the separate recording of neuroelectrical signals, ECG, and respiration waves. An additional software program, also developed by our group, was used to analyze the data. This chronic animal model allows investigation of surgical and pharmacological manipulations of the sympathetic system.