15-hydroxy-5-8-11-13-eicosatetraenoic-acid and Rhinitis--Allergic--Perennial

The responses to airway hyperosmolar challenges probably involve various inflammatory mediators. However, it is not fully understood which cell type/types are the source of these mediators. Potential cell types include mast cell, epithelial cell and the sensory c-fibre nerve cell.. To clarify which cell types are involved with the mediator response to hyperosmolarity in the human airway.. Ten healthy subjects, 11 patients with nonactive allergic rhinitis, and nine with active allergic rhinitis were challenged intranasally with mannitol powder, and with sham provocation, on separate days. Symptoms were assessed by visual analogue scales and nasal patency by measuring the nasal peak inspiratory flow (nPIF). Nasal lavage fluid levels of alpha(2)-macroglobulin (an index of plasma extravasation), substance P (an index of sensory nerve cell activation), tryptase (an index of mast cell activation) and 15-hydroxyeicosatetraenoic acid (15-HETE, an index of epithelial cell activation) were analysed.. Immediate, although transient burning was the most prominent symptom in all groups whereas only the patients with active rhinitis experienced a fall in nPIF. Mannitol significantly increased the nasal lavage fluid 15-HETE levels in the allergic patients (P < 0.01 vs the sham challenge), but not in the healthy subjects. The increase in 15-HETE correlated with nasal symptoms for itching (r(s) = 0.65, P = 0.019) and burning (r(s) = 0.72, P = 0.009). Detectable levels of tryptase was found only in five allergic subjects. Lavage levels of substance P and alpha(2)-macroglobulin did not not change.. Epithelial cell seems to be involved with the mediator response to airway hyperosmolar challenge. The roles of sensory c-fibre nerve cell and mast cell remained less clear.

Topics: Adult; alpha-Macroglobulins; Epithelial Cells; Female; Humans; Hydroxyeicosatetraenoic Acids; Hypertonic Solutions; Inspiratory Capacity; Male; Mannitol; Mast Cells; Nasal Lavage Fluid; Nasal Mucosa; Nasal Provocation Tests; Nerve Fibers; Powders; Rhinitis, Allergic, Perennial; Serine Endopeptidases; Sneezing; Spirometry; Substance P; Tryptases

The purpose of this study is to examine the "in vivo" release of 15-HETE and other arachidonic acid metabolites in nasal secretions following a challenge with "Dermatophagoides Pteronyssinus" in patients with allergic rhinitis and non-allergic controls. In addition, we examine the effects of a membrane stabilizer, such as sodium cromoglycate, on these metabolites. Thirteen allergic subjects and seven healthy controls are studied. 15-HETE, peptide leukotrienes, LTB4, PGD2, PGE2 and PGF2 alpha levels are evaluated before and after nasal challenge in sodium cromoglycate treated and untreated subjects. This study provides "in vivo" evidence that the pathophysiological responses to nasal antigen challenge could be related to the release of 15-HETE as well as other arachidonic acid metabolites, mainly arising from the lipoxygenase pathway.

Topics: Adolescent; Adult; Analysis of Variance; Arachidonic Acid; Cromolyn Sodium; Dinoprost; Dinoprostone; Female; Humans; Hydroxyeicosatetraenoic Acids; Leukotriene B4; Lipoxygenase; Male; Middle Aged; Nasal Mucosa; Nasal Provocation Tests; Prostaglandin D2; Rhinitis, Allergic, Perennial