Characterization of airway and vascular responses in XXXX lungs.

@entity2871 @entity859 @entity19 @entity2872 @entity2786 @entity2507 @entity10501 @entity750 @entity112 @entity2710 @entity15486 @entity6138
1. We characterized the responses of @entity19 airways and pulmonary vessels to a variety of endogenous mediators in the isolated perfused and ventilated @entity19 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 @entity2710 (Mch), 6.1/1.5> @entity750 , 0.7/2.0> @entity2872 (TP-receptor agonist), 0.1/0.06> @entity15486 , 0.1/0.05. In the IPL, maximum increase in airway resistance (RL) was 0.6, 0.4, 0.8 and 11 cm @entity2507 s ml(-1), respectively. @entity859 (< or =1 mM), @entity6138 (< or =100 microM), @entity112 (< or =10 mM), LTC4 (< or =1 microM), PAF (0.25 microM) and @entity10501 (< 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> @entity2872 , 0.05< @entity15486 , 0.02. The maximum increase in pulmonary artery pressure (PAP) was 11, 41 and 48 cm @entity2507 , respectively. At 250 nM, the activity of PAF was comparable to that of LTC4. At 100 microM only, @entity10501 caused a largely variable increase in @entity2786 . @entity750 , @entity859 , @entity6138 , @entity112 and Mch had no or only very small effects on PAP. 4. Hyperresponsiveness: In both the IPL and slices, @entity2872 in subthreshold concentrations (10 nM) reduced the EC50 to 0.6 microM. In the IPL, @entity2872 raised the maximum airway response to Mch 5 fold and the maximum PAF-induced vasoconstriction 4 fold. 5. CONCLUSION: @entity19 precision-cut lung slices maintain important characteristics of the whole organ. The maximum reagibility of @entity19 airways to endogenous mediators is @entity750 <Mch< @entity2872 <ET-1. The reagibility of the @entity19 pulmonary vasculature is @entity750 <LTC4 approximately = to PAF< @entity2872 <ET-1. The airway and vessel hyperreactivity induced by @entity2872 raises the possibility that @entity2871 contributes directly to airway hyperresponsiveness in various experimental and clinical settings.
