Hypoxia and iodoacetic acid and alveolocapillary barrier permeability to albumin.

GOODALE, ROBERT L., BOYD GOETZMAN, AND MAURICE B. VISSCHER. Hypoxia and ioduacetic acid and alveohzpillary barrier permeability to albumin, Am. J. Physiol. 219(5): 12264230. 1970Perfusion studies at controlled flow rates using the isolated left lower lobe of the canine lung were performed under normal oxygen tensions and under conditions of low 0, tension, averaging 12 mm Hg. The average permeability coefficient of the alveolocapillary membrane to serum albumin -1311 placed in Tyrode solution-filled alveoli was calculated to be 2.85 cm se@ x 1 O* based on vascular appearance rates. This absolute value has uncertainties which are enumerated. Under conditions of marked hypoxia, there was no significant effect upon the appearance rates or the calculated permeability of the alveolocapillary membrane during the periods studied. When sodium iodoacetate, 2 IXLM, was added to the fluid perfusing the hypoxic lungs, however, an increase in appearance rates and permeability was detected within 22 min and became progressively greater with time. The average observed maximum increase in permeability was 36 times the control. It is concluded that this poison causes an increase in alveolocapillary permeability to protein.