Localization of H2S-producing enzymes in the myenteric plexus of rat duodenum. (A) The triple-labelling of NeuN, CBS and SM22 of LMMP. CBS was expressed in NeuN-positive neurons but not SM22-immunoreactive smooth muscle cells. (B) With CBS antibody from Santa Cruz and (C) CBS antibody from Abcam, show the photos taken of the myenteric plexus. It is clear that in the myenteric plexus, all NeuN-immunoreactive cells were CBS-positive. (D) The triple-labelling of NeuN, CSE and SM22 of LMMP. CSE was expressed in NeuN-positive neurons but not in the smooth muscles. (E) The double labelling of NeuN and CSE of the myenteric plexus (CSE antibody from Abcam). All NeuN-positive cells expressed CSE. (F) A myenteric ganglion with double labelling of CBS and CSE (CSE antibody from Santa Cruz). In this ganglion, all the CSE-positive cells were also CBS-positive. Scale bars are 50 μm.