Histamine content, synthesis and degradation in human nasal mucosa

Abstract

Histamine content and enzyme activities of histamine metabolism, histidine decarboxylase (HDC), histamine N-methyltransferase (HMT) and histaminase (diamine oxidase, DAO) in human nasal mucosa were determined with a highly sensitive and specific fluorescent method which was combined with high performance liquid chromatography. Histamine content and HDC activity were determined in 10 specimens of nasal polyp, nine specimens of maxillary sinus and five specimens of inferior turbinate. HMT and histaminase activities were determined in 15 specimens of nasal polyp, nine specimens of maxillary sinus and five specimens of inferior turbinate obtained during surgical therapy. Histamine and activities of HDC, HMT and histaminase were detected in all specimens except the case of histaminase activity in one specimen of nasal polyp. The mean values of histamine content and activities of HDC, HMT and histaminase of human nasal mucosa were 137.3 nmol/g wet weight, 26.3 fmol/min/mg protein, 26.4 pmol/min/mg protein and 0.5 pmol/min/mg protein, respectively. Histamine content in the mucosal tissue of the maxillary sinuses was significantly higher than that of nasal polyps or inferior turbinates. There were no significant differences in HDC activities among three kinds of nasal mucosa. Activities of HMT and histaminase, including their kinetic constants (Km and Vmax values for histamine) indicated that HMT has a greater potential than histaminase for histamine degradation in the human nasal mucosa. The presence of these enzymes suggests that these activities constitute an important modulating factor in histamine mediated allergic and inflammatory reactions in human nasal mucosa.

Histamine, histamine receptors and their role in immune pathology

“…IgE binding to the FcɛRI on IL‐3‐dependent mouse bone marrow‐derived mast cells induces the expression of HDC through a signalling pathway different from that operating during antigen‐stimulated FcɛRI activation [32]. More than 97% of the histamine is metabolized in two major pathways before excretion [33]. Histamine N ‐methyltransferase metabolizes the majority of histamine to N ‐methylhistamine, which is further metabolized to the primary urinary metabolite M‐methylimidazole acetic acid by monoamine oxidase.…”

Concentrations of H1-Receptor Antagonist in the Human Nasal Mucosa

“…In fact, there were many reports on the tissue concentration of antimicrobial and anticancer drugs in the human nasal and paranasal region [5–7]. Histamine is an important chemical mediator in allergic rhinitis and plays an important role in eliciting the nasal symptoms of the disorder [8]. H1-receptors are also known to exist on the postcapillary venules in nasal mucosa to induce vasodilation, to increase vascular permeability, and to stimulate sensory nerve endings in response to histamine [9].…”

Regulatory Effects of Histamine and Histamine Receptor Expression in Human Allergic Immune Responses

“…IgE binding to the FcεRI on IL-3-dependent mouse bone marrow-derived mast cells induces the expression of HDC through a signaling pathway distinct to that operating during antigen-stimulated FcεRI activation (24). More than 97% of the histamine is metabolized in 2 major pathways before excretion (25). Histamine Nmethyltransferase metabolizes the majority of histamine to N-methylhistamine, which is further metabolized to the primary urinary metabolite M-methylimidazole acetic acid by monoamine oxidase.…”