[New aspects in the pathogenesis and therapy of hyperreflexive rhinopathy]

Abstract

Hyperreflectory rhinopathy (HR) is a non-specific hyperreactivity of the nasal mucosa. It causes hypersecretion, decreased nasal patency, sneezing and sometimes headache by local reflexes, which are beyond voluntary control. The synonymous name "vasomotor rhinitis" or "vasomotor rhinopathy" is no longer adequate with regard to our present state of knowledge of the autonomous innervation of the human nasal mucosa. Recent pharmacological investigations show the great importance of peptidergic neurons. In our own studies, the presence and the topical effects of the neuropeptide substance-P in human nasal mucosa are examined. A new concept of the autonomous innervation of the human nasal mucosa is presented. Apart from adrenergic and cholinergic neurons, it also includes peptidergic neurons (SP, CGRP, NKA, VIP, PHI, APP, GRP). According to this model, a hypothesis on the pathogenesis of HR is developed. A key position is occupied by the so-called "axon reflex" which is mediated by substance-P immunoreactive nerve fibers. It is released by a chemical, thermal or mechanical irritation. This axon reflex mediates pain, vasodilation and plasma extravasation (neurogenic oedema), hypersecretion such as smooth muscle contraction, and sneezing reflex. Capsaicin (8-methyl-N-vanillyl-6-nonenamid) leads to a selective degeneration of substance-P immunoreactive nerve fibres and desensitisation of its receptors after repeated topical or systemic application, thus blocking the axon reflex. The risk-free application of capsaicin was shown in self-experiments and in volunteers. Our hypothesis was confirmed by the good results of the treatment of a group of volunteer patients who suffered from HR.(ABSTRACT TRUNCATED AT 250 WORDS)