Angiotensin-converting enzyme inhibitors actions

Cushman, D. W., Cheung, H. S., Sabo, E. F., and Ondetti, M. A. (1981). Angiotensinconverting enzyme inhibitors Evaluation of a new class of antihypertensive drugs. In "Angiotensin-Converting Enzyme Inhibitors Mechanism of Action and Clinical Implications", (Z. P. Horovitz, Ed.), pp. 1-25. Urban and Schwarzenberg, Baltimore and Munich. 

Ondetti, M.A. and Cushman, D.W. 1984. Angiotensin-converting enzyme inhibitors biochemical properties and biological actions. CRC Crit. Rev. Biochem. Mol. Biol. 16, 381-411. 

Petrillo, E.W. and Ondetti, M.A. 1982. Angiotensin-converting enzyme inhibitors, medical chemistry and biological actions. Med. Res. Rev. 2, 1-41. 

Petrillo, E. W., Ondotti, M. A., Angiotensin-Converting Enzyme Inhibitors Medicinal Chemistry and Biochemical Actions, Medicinal Res. Rev. 2 1-41, 1982. 

Figure 11-4. Actions of angiotensin-converting enzyme inhibitors and AT receptor blockers. The enzyme is responsible for activating angiotensin by conversion of angiotensin I to angiotensin II and for inactivating bradykinin, a vasodilator normally present in very low concentrations. Block of the enzyme thus decreases the concentration of a vasoconstrictor and increases the concentration of a vasodilator. The AT, receptor antagonists lack the effect on bradykinin levels, which may explain the lower incidence of cough observed with these agents.

C. Clinical Role Although it has no therapeutic application, bradykinin may play a role in the antihypertensive action of angiotensin-converting enzyme inhibitors, as previously noted (Chapter 11 Figure 11-4). At present there are no clinically important bradykinin antagonists. 

NSAIDs interfere with the antihypertensive action of angiotensin-converting enzyme inhibitors the other drugs listed enhance the blood pressure-lowering effects of captopril and other members of the pril drug family. The answer is (C). 

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