Distribution of Neuropeptides in Nasal Polyp and Polypoid Mucosa

Ko, Pil Jun; Rha, Ki Sang; Park, Chan Il

Abstract

BACKGROUND: The pathogenesis of nasal polyp is not well understood, however the common pathway of nasal polyp formation is tissue edema. Factors that are known to predispose tissue edema include histamine, arachidonic acid metabolites, serotonin and peptidergic neuro-transmitters.
OBJECTIVES
To elucidate the pathophysiological roles of peptidergic neurotransmitters on the polyp formation, we investigated the distribution of several immunoreactive nerve fibers.
MATERIALS AND METHODS
We obtained normal middle turbinate mucosa, edematous middle turbinate mucosa, polypoid middle turbinate mucosa and nasal polyp tissue from 5 patients at the time of surgery and we determined the distribution of substance P(SP) immunoreactive, vasoactive intestinal peptide(VIP) immunoreactive and neuropeptide-Y(NPY) immunoreactive nerve fibers in the above tissues using avidin-biotin complex(ABC) immunohistochemical method.
RESULTS
Fine varicose peptidergic nerve fibers were found numerously in normal mucosa and they were decreased in number in the edematous mucosa. However the peptidergic nerve fibers were hardly found in the polypoid mucosa and the pedicle of polyp, and no nerve fibers were found in the apex of polyp except VIP-immunoreactive nerve fibers.
CONCLUSION
Decreasing tendency of distribution of these peptidergic nerve fibers in the order of edematous mucosa, polypoid mucosa, and polyp may indicate the denervation of autonomic nervous system. These phenomenon suggests the important role of peptidergic neurotransmitters in the early stage of polyp formation. However, once the polyp has been formed, contribution of the peptidergic neurotransmitters is considered to be negligible.