Invasive versus noninvasive measurement of allergic and cholinergic airway responsiveness in mice.
BACKGROUND
This study seeks to compare the ability of repeatable invasive and noninvasive lung function methods to assess allergen-specific and cholinergic airway responsiveness (AR) in intact, spontaneously breathing BALB/c mice.


METHODS
Using noninvasive head-out body plethysmography and the decrease in tidal midexpiratory flow (EF50), we determined early AR (EAR) to inhaled Aspergillus fumigatus antigens in conscious mice. These measurements were paralleled by invasive determination of pulmonary conductance (GL), dynamic compliance (Cdyn) and EF50 in another group of anesthetized, orotracheally intubated mice.


RESULTS
With both methods, allergic mice, sensitized and boosted with A. fumigatus, elicited allergen-specific EAR to A. fumigatus (p < 0.05 versus controls). Dose-response studies to aerosolized methacholine (MCh) were performed in the same animals 48 h later, showing that allergic mice relative to controls were distinctly more responsive (p < 0.05) and revealed acute airway inflammation as evidenced from increased eosinophils and lymphocytes in bronchoalveolar lavage.


CONCLUSIONS
We conclude that invasive and noninvasive pulmonary function tests are capable of detecting both allergen-specific and cholinergic AR in intact, allergic mice. The invasive determination of GL and Cdyn is superior in sensitivity, whereas the noninvasive EF50 method is particularly appropriate for quick and repeatable screening of respiratory function in large numbers of conscious mice.
Glaab
Thomas
T
Fraunhofer Institute of Toxicology and Experimental Medicine, Nikolai-Fuchs Str. 1, 30625 Hannover, Germany. thomasglaab@web.de
Ziegert
Michaela
M
Baelder
Ralf
R
Korolewitz
Regina
R
Braun
Armin
A
Hohlfeld
Jens M
JM
Mitzner
Wayne
W
Krug
Norbert
N
Hoymann
Heinz G
HG
D000485:Allergens; D000818:Animals; D001985:Bronchial Provocation Tests / Q000379:methods*; D005260:Female; D016210:Methacholine Chloride; D051379:Mice; D008807:Mice, Inbred BALB C; D010991:Plethysmography / Q000379:methods*; D015203:Reproducibility of Results; D012129:Respiratory Function Tests / Q000379:methods*; D012680:Sensitivity and Specificity
D000485:Allergens; D016210:Methacholine Chloride