Which of the following is inactivated in the lung?
High-Yield Explanation
Vasoactive substances on their passage through the lungs are completely or paially inactivated. Bradykinin is a potent vasodilator that is not synthesized in the lung, but is largely inactivated in the pulmonary endothelium following degradation by angiotensin conveing enzyme. About 80% of bradykinin is inactivated in the lung. The lung is also the major site of inactivation of serotonin but this is by uptake and storage process not by enzymatic degradation. Angiotensin I is conveed to angiotensin II by angiotensin conveing enzyme (ACE). There is no effect on angiotensin II and vasopressin. Ref: Respiratory physiology, By John B West, 9th Edition, Page 52.