SEROTONIN AND ITS POSSIBLE ROLE IN THE PAINFUL NON-INFLAMED APPENDIX

  • 1 January 1983
    • journal article
    • research article
    • Vol. 6  (3-4) , 239-246
Abstract
After immunohistochemical staining, appendices without active inflammation but producing symptoms of appendicitis (n = 24 [human]) were compared with a control group of appendices removed incidental to another procedure (n = 26). Staining for neuron specific enolase (NSE) showed more instances of nerve hyperplasia in the control group than in the appendices generating pain refuting the concept of neuroappendicopathy based on quantitative nerve changes. Serotonin staining identified subepithelial neuroendocrine cells (SNC) in 85% of the specimens. All cases showed serotonin immunoreactive enterochromaffin cells (EC). Staining for serotonin was significantly decreased in the SNC in the painful group. There were no significant differences between the 2 groups in staining intensity of SNC and EC for substance P (SP). Vasoactive intestinal polypeptide (VIP) was not seen in the SNC and EC and there were no differences in nerve fiber staining for VIP. Serotonin is a neurotransmitter as well as mediator of inflammation. Reduced staining for serotonin in painful appendices may reflect discharge of stores which could be instrumental in inducing the pain in these cases. Continued serotonin release may then lead to acute appendicitis.