CHANGES OF PROTEIN GENE-PRODUCT-9.5 (PGP-9.5) IMMUNOREACTIVE NERVES IN INFLAMED APPENDIX

The existence of chronic appendicitis is controversial. In this prospe ctive study, we investigated possible changes in the innervation of th e appendix under different pathological conditions and correlated hist ological findings with clinical observation. Thirty appendectomy speci mens and 14 appendices obtained from organ donors or patients who unde rwent right hemicolectomy were immediately fixed in Bouin's solution a nd processed for immunocytochemistry using an antiserum directed again st the panneuronal marker protein gene product 9.5 (PGP 9.5). The dens ity of PGP 9.5 immunostaining was evaluated by digitized morphometry. Significant differences in the density of the PGP 9.5-immunoreactive a rea were detected in the mucosal layer. In the nonacute appendicitis g roup, PGP 9.5- was increased (10.99 +/- 3.15%) as compared to acute ap pendicitis (3.89 +/- 1.77%) and controls (4.98 +/- 1.25%). The signifi cant increase of PGP 9.5 in nonacute appendicitis may suggest axonal s prouting leading to hyperinnervation of the mucosa. This may be a neur onal factor in the pathophysiology of the disease and pain symptoms.