IN VITRO RESPIRATION OF NORMAL AND PATHOLOGIC HUMAN LUNG.

Abstract

The Qo2 of normal and pathologic human pulmonary tissue was measured according to the direct method of Warburg. Lung specimens were reduced to rods of intact cells in their normal architectural relationships by the McIlwain chopper. This instrument is thought to eliminate the problem of erratic and incomplete diffusion of oxygen into the preparation by virtue of the fact that tissue can be subdivided into uniformly thin units, well within maximum allowable dimensions as determined by Warburg. Quantitation solely of actively respiring elements by the point-counting method of Chalkley permitted comparison of respiratory rate of normal with abnormal pulmonary tissue and eliminated the problem in calculation of Qo2 of dilution of pathologic material with normal cells and necrotic, nonrespiring elements. Oxygen consumption values for normal, tuberculous, and malignant lung were, respectively, 2.1, 5.4, and 8.6 μl O2/mg dry wt. per hr, suggesting that the oxidative metabolism in tuberculous inflammation and malignancy primary in the lung is elevated significantly. Possible sources of this augmented metabolic rate are discussed. lung tissue metabolism; human pulmonary tissue respiration; tuberculous lung tissue metabolism; lung carcinoma tissue metabolism; lung tissue preparation Submitted on September 19, 1963