Specific impedance of longitudinal and circular muscle from cat proximal jejunum

Abstract

Although electron microscopic studies have demonstrated the presence of gap junctions or nexuses between smooth muscle cells of the circular muscle layer of the small intestine, they have failed to reveal any significant number of nexuses between muscle cells in the longitudinal layer^1,2. if the gap junction is involved in electrically coupling smooth muscle cells, one would expect to find an inverse relationship between the number of such junctions and the specific junctional impedance of the tissue. In the case of the intestine, circular muscle would be expected to have a considerably lower specific junctional impedance than longitudinal muscle. We investigated this relationship using a modification of a method for measuring tissue impedance originally devised by Tomita³.