Ethanol‐ and isoprenaline‐induced responses in pig parenchymal lung tissue

Ethanol (8·7–34·8 mm; 0·5–0·20% v/v) had no significant effect on spontaneously developed tension in pig lung parenchyma strips, although higher cumulative concentrations caused relaxation (at 34·8–174 mm) and contraction (at 348–1392 mm). Ethanol‐induced effects were not caused by activation of adrenoceptors or of cholinoceptors, since blockade of these receptors did not alter those effects. Single low concentrations of ethanol (8·7–34·8 mm) which can occur in‐vivo in man, caused increases in the relaxant potency of isoprenaline in pig lung strips, although the sizes of these increases varied widely. In addition, ethanol‐induced potentiation of isoprenaline was not concentration‐related. This effect was not caused by inhibition of isoprenaline uptake since [3H]isoprenaline transport was found not to be significantly altered in the presence of ethanol (8·7–34·8 mm).