Characterization of airway and vascular responses in murine lungs

1. We characterized the responses of murine airways and pulmonary vessels to a variety of endogenous mediators in the isolated perfused and ventilated mouse lung (IPL) and compared them with those in precision-cut lung slices. 2. Airways: The EC50 (microM) for contractions of airways in IPL/slices was methacholine (Mch), 6.1/1.5>serotonin, 0.7/2.0>U46619 (TP-receptor agonist), 0.1/0.06>endothelin-1, 0.1/0.05. In the IPL, maximum increase in airway resistance (RL) was 0.6, 0.4, 0.8 and 11 cmH2O s ml(-1), respectively. Adenosine (< or =1 mM), bombesin (< or =100 microM), histamine (< or =10 mM), LTC4 (< or =1 microM), PAF (0.25 microM) and substance P (< or =100 microM) had only weak effects (<5% of Mch) on RL. 3. Vessels: The EC50 (microM) for vasoconstriction in the IPL was LTC4, 0.06>U46619, 0.05

Murine precision-cut lung slices maintain important characteristics of the whole organ. The maximum reagibility of murine airways to endogenous mediators is serotonin