The diseased lung and drugs.
Among the numerous ways by which drug-lung relationships can be discussed we chose to examine three questions: Is the lung capable of directly modulating drug pharmacokinetics? Knowing that the pulmonary circulation can exert very selective and efficient clearance and catabolism of biogenic molecules such as serotonin (5-HT), norepinephrine (N.E.), prostaglandins PGE2 and PGF2 alpha, and bradykinin, as well as activation of angiotensin (A)I to AII, a similar behavior has been sought for drugs. Uptake of circulating drugs occurs clearance of biogenic amines, the significance of which remains to be fully evaluated, and iatrogenic phospholipidosis localization of which in the lung might result from the elevated drug concentration in the tissue. Lung cells contain enzymes, among them mixed function oxidases (MFO), which enables them to metabolize xenobiotics even in the intact organ. Although blood supply to the lung is higher than that to the liver, the comparatively low MFO content of the former organ predicts only a marginal pulmonary metabolic contribution in vivo. On the otherhand, enzymatic activity upon drugs can generate instable reactive metabolites which, even in minute amounts are toxic and can damage cells; furthermore, it is hypothesized that the relatively high bronchiolar Clara cell MFO content explains the striking susceptibility of the long to xenobiotics. Do lung diseases indirectly influence drug pharmacokinetics? Hindrance to blood flow is common in respiratory failure (R.F.), from both reduced area and hypoxic vasoconstriction, resulting in altered flow distribution to the liver and kidney.
D064420:Drug-Related Side Effects and Adverse Reactions; D006801:Humans; D007700:Kinetics; D008168:Lung / Q000378:metabolism; D008171:Lung Diseases / Q000378:metabolism / Q000503:physiopathology*; D004364:Pharmaceutical Preparations / Q000378:metabolism; D011652:Pulmonary Circulation / Q000187:drug effects
D004364:Pharmaceutical Preparations