Alveolar liquid and protein clearance in anesthetized ventilated rats

and M. A. Matthay. Alveolar liquid and protein clearance in anesthetized ventilated rats. J. Appl. Physiol. 76(6): 2636-2642, 1994.-Alveolar and lung liquid clearances were studied over 1, 4, and 6 h in intact anesthetized ventilated rats by instillation of 5 % albumin solution with 1.5 &i of 1251-labeled albumin (3 ml/kg into 1 lung or 6 ml/kg into both lungs). Alveolar protein clearance as measured by residual ‘251-albumin in the lung over 6 h was similar to the slow rates measured in other species. Alveolar liquid clearance was estimated by the concentration of albumin in the air spaces. After 1 h, this concentration was 7.8 + 0.7 g/dl, which was significantly greater than the initial-protein concentration of 5.3 t 0.2 g/d1 (P < 0.05). Amiloride (10B3 M) inhibited 45 % of the basal alveolar liquid clearance, and ouabain (10e3 M), instilled and intravenously infused (0.004 mg), inhibited 30 % of the clearance. P-Adrenergic ago