Pharmacokinetics—A Physiological Function of Lung

Abstract

Boyle recognized the “genuine use of Respiration as the Ventilation of the Blood in its passage thorow the Lungs; in which passage it is disburthened of Excrementitious Steams” (Boyle, 1660) and Lower a few years later came to the additional conclusion that “the blood takes in air in its course through the lungs and owes its bright colour entirely to the admixture of air” (Lower, 1669). Ever since then investigations into the function of lung have concentrated on respiratory gas exchange. Only comparatively recently have some nonrespiratory functions of lung, for instance, its ability to act as a reservoir of blood and its ability to filter cellular debris from blood, been recognized and lucidly summarized by Heinemann and Fishman (1969). The newest function of lung to be studied is its ability to alter the biological activity of substances entering the lung either through the airways or, more importantly, through the pulmonary circulation. This ability has been called, for want of a better phrase, the pharmacokinetic function of lung (Bakhle and Vane, 1974), and it is this function that is discussed here.