CORTICOSTEROID WITHDRAWAL RESTORES RESPONSES TO CALCIUM CHELATORS ANDENHANCES CHOLINERGIC RESPONSIVENESS

Citation
Ks. Lindeman et Ca. Hirshman, CORTICOSTEROID WITHDRAWAL RESTORES RESPONSES TO CALCIUM CHELATORS ANDENHANCES CHOLINERGIC RESPONSIVENESS, The American review of respiratory disease, 148(6), 1993, pp. 1581-1585
Citations number
40
Categorie Soggetti
Respiratory System
ISSN journal
00030805
Volume
148
Issue
6
Year of publication
1993
Pages
1581 - 1585
Database
ISI
SICI code
0003-0805(1993)148:6<1581:CWRRTC>2.0.ZU;2-0
Abstract
To investigate the importance of the inflammatory response in acute pe ripheral airway constriction, we measured peripheral airway responses to calcium chelators and acetylcholine in anesthetized Basenji-Greyhou nd (BG) dogs before, during, and after chronic corticosteroid treatmen t. A wedged bronchoscope technique was used to measure peripheral airw ay resistance before and after aerosol challenge with 4% Na,EDTA or ac etylcholine (10 mu g/ml) in contralateral lungs. After the initial mea surements, five BG dogs received long-term treatment with methylpredni solone (2 mg/kg/d, subcutaneously), and five dogs were not treated and served as controls. Four weeks of methylprednisolone treatment almost totally abolished responses to Na(2)EDTA, but responses to acetylchol ine did not change significantly. After discontinuing corticosteroid t herapy, responses to Na(2)EDTA returned to levels found before cortico steroid treatment; responses to acetylcholine were significantly enhan ced. We conclude that chronic corticosteroid treatment reduces acute r esponse to calcium chelators and that withdrawal of corticosteroid the rapy is associated with enhanced cholinergic responsiveness.