Effects of beta-endorphin on nasal allergic inflammation.
BACKGROUND
Beta-endorphin is a derivative of pro-opiomelanocortin. Cells of the immune system can also synthesize and secrete beta-endorphin. Its concentration is increased during the allergic reaction and during stress. Increased reactivity during psychological stress of allergic subjects is also well known.


OBJECTIVE
Is beta-endorphin one physiological link between stress and an exacerbation of the allergic reaction?


METHODS
First, intranasal beta-endorphin challenges with subsequent lavages to determine histamine and albumin levels and measurements of nasal flow and resistance in dose-response and time course experiments were performed. Secondly, we examined whether beta-endorphin pre-treatment increased the antigen-induced release of histamine and albumin in nasal lavages and the clinical symptoms.


RESULTS
Exogenous beta-endorphin (100 pM-10 microM/mL) induced a dose-dependent increase in nasal symptoms in asymptomatic allergic subjects with rhinitis (n = 14) as well as in non-allergic controls (n = 10), but did not release any mediators into nasal secretion. However, comparing the antigen-evoked release of mediators into nasal secretions with that of a beta-endorphin pre-treated antigen challenge we could note a significant enhancement of human serum albumin influx (P < 0.05) and histamine liberation (P < 0.05) 10 min after antigen challenge compared with the allergen challenge alone, with also a correlation with the more pronounced decrease in nasal flow (P < 0.05).


CONCLUSIONS
These results suggest that beta-endorphin-induced increase in nasal congestion is mediated through direct neuroendocrine receptor activation independent of mast cell activation and that during the allergic reaction there is a beta-endorphin/mast cell interaction that enhances the mediator response to nasal allergen challenge.
Baumgarten
Claus R
CR
Charité, Campus Virchow-Klinikum, Allergy and Asthma Clinic, Humboldt University Berlin, Augustenburger Platz 1, 13353 Berlin, Germany. claus.baumgarten@charite.de
Schmitz
P
P
O'Connor
A
A
Kunkel
G
G
D000280:Administration, Inhalation; D000328:Adult; D000485:Allergens / Q000276:immunology; D000941:Antigens / Q000276:immunology; D004305:Dose-Response Relationship, Drug; D005260:Female; D006636:Histamine Release / Q000187:drug effects; D006801:Humans; D008297:Male; D008875:Middle Aged; D009296:Nasal Cavity / Q000503:physiopathology; D017817:Nasal Lavage Fluid / Q000737:chemistry; D015508:Nasal Obstruction / Q000139:chemically induced / Q000503:physiopathology; D012016:Reference Values; D012221:Rhinitis, Allergic, Perennial / Q000503:physiopathology*; D012709:Serum Albumin / Q000378:metabolism; D001615:beta-Endorphin / Q000008:administration & dosage* / Q000494:pharmacology
D000485:Allergens; D000941:Antigens; D012709:Serum Albumin; D001615:beta-Endorphin