Regeneration of ’ Auerbach ’ S Plexus in the Small Intestine

N a previous communication l on this subject from Dr. Carlson’s laboratory, it was shown that after transection of the small intestine? physiological restoration, as determined by the passage of a peristaltic wave across the lesion, could be demonstrated as enrly as the eighth day. On closer ana1ysi.s this peristaltic wave was found to depend for its transmission on a purely mechanical fac&or, the tug of the musculature at the line of transection. The passage of a wave of contraction was thus shown to be in.sufficient as a test for the regeneration of the nervous motor mechanism of the intestine. Recourse was then had to histological methods. By means of the gold chloride stain regeneration of certain fibr,es in Auerbach’s plexus was shown in one of six dogs, one hundred and eighty days after transection. Unfortunately the origin of the fibres was not definitely known l Instead of being outgrowths of nerve cells in the intestinal plexus, they might have been postganglionic axones from extrinsic abdominal ganglia. The problem has been taken up anew in hopes of being able to demonstrate conclusively a regeneration of the plexus of Auerbach accompanied by a return of complete physiological function. Regeneration has therefore been tested both histologically and physiologically. Histologically the gold chloride stain was again used and reduction brought about in arsenic acid. A more complete description of the technique will be found in the protocols. Physiologically regeneration has been tested by the passage of a wave of inhibition through the transected areas. Bayliss and Starling 2 in their well-known papers have shown that the contraction