Subservient relationship between central and peripheral augmentation indexes in normal and KHC rabbits

Abstract

It is still unclear to what extent augmentation index (AIx) of peripheral pressure waves reflects that of central pressure waves in response to change in blood pressure level in the presence of atherosclerosis. We investigated subservient relationship between AIxs from central and peripheral pressure waves in the normal and Kurosawa and Kusanagi-hypercholesterolemic (KHC) rabbits aged 12 months. Changes in pressure waves in response to intravenous infusion of angiotensin II (Ang II) and sodium nitroprusside (NTP) were simultaneously recorded at the ascending aorta (AA) and distal end of the right brachial artery (Br) using two catheter-tip transducers under pentobarbital anesthesia. AIx at Br changed in parallel with that at AA during pressor and depressor responses to Ang II and NTP in the two rabbit groups, respectively. AIxs at AA and Br were significantly greater in the KHC rabbit group than in the control rabbit group at the same high blood pressure level during Ang II infusion. We can conclude that changes in AIx of the central pressure waves induced by vasoactive agents are followed by those of the peripheral pressure waves in the two rabbit groups, and that AIx at the peripheral artery well reflects the increased AIx at the central artery due to atherosclerosis in KHC rabbits. [J Physiol Sci. 2008;58 Suppl:S183]