[Nitric-oxidergic mechanisms in the regulation of the bronchi and their significance in the pathogenesis of bronchial asthma].
OBJECTIVE
Assessment of NO-synthase (NOS) activity in bronchial asthma (BA) basing on cytochemical identification and quantitation of NADPN-diaphorase.


METHODS
Operative samples from 12 BA patients and biopsies from 8 patients free of bronchial inflammation or obstruction. Experimental data on control and BA rat males injected either with NOS agonist acetyl choline (AC) or beta-2-agonist fenoterol (F).


RESULTS
A direct relationship was found between BA severity and activity of NADPN-diaphorase resultant from activation of inducible NOS (iNOS) mediating constrictive effect via different cellular and humoral mechanisms. AC treatment caused bronchial relaxation and severe constriction in control and BA rats, respectively, though NADPN-diaphorase activity was enhanced in both groups. Introduction of F brought about bronchial relaxation in both groups. However, there were some cases of constriction in the bronchi with impaired epithelium and high baseline iNOS activity.


CONCLUSIONS
In intact bronchial epithelium, administration of cholino- and adrenoreceptors agonists induced bronchial myocyte relaxation due to activation of constitutive NOS. In impaired bronchial epithelium, AC stimulates iNOS induction provoking severe constriction of small bronchi.
Nevzorova
V A
VA
Eliseeva
E V
EV
Zuga
M V
MV
Protopopova
M Iu
MIu
Gel'tser
B I
BI
D000109:Acetylcholine / Q000494:pharmacology; D000318:Adrenergic beta-Agonists / Q000494:pharmacology; D000818:Animals; D001249:Asthma / Q000209:etiology* / Q000378:metabolism; D001980:Bronchi / Q000187:drug effects / Q000378:metabolism*; D004195:Disease Models, Animal; D004305:Dose-Response Relationship, Drug; D005280:Fenoterol / Q000494:pharmacology; D006651:Histocytochemistry; D006801:Humans; D066298:In Vitro Techniques; D008297:Male; D009252:NADPH Dehydrogenase / Q000378:metabolism; D009569:Nitric Oxide / Q000378:metabolism*; D019001:Nitric Oxide Synthase / Q000037:antagonists & inhibitors / Q000378:metabolism; D052247:Nitric Oxide Synthase Type II; D051381:Rats; D011956:Receptors, Cell Surface / Q000378:metabolism*
D000318:Adrenergic beta-Agonists; D011956:Receptors, Cell Surface; D005280:Fenoterol; D009569:Nitric Oxide; C496319:NOS2 protein, human; D019001:Nitric Oxide Synthase; D052247:Nitric Oxide Synthase Type II; C496318:Nos2 protein, rat; D009252:NADPH Dehydrogenase; D000109:Acetylcholine
Nitrooksidergicheskie mekhanizmy reguliatsii bronkhov i ikh znachenie v patogeneze bronkhial'noĭ astmy.