Heart Rate Variability in Conscious and Anesthetized Rats under the Action of Angiotensin Converting Enzyme Inhibitors

Abstract

We studied the effects of three various angiotensin converting enzyme inhibitors (enalapril, lisinopril and quinapril) on heart rhythm variability in anesthetized and immobilized rats. In all cases (except for quinapril in experiments on anesthetized animals), the preparations reduced the total rhythm variability and, according to spectrum analysis, increased activity of the parasympathetic autonomic nervous system to different degrees and decreased sympathetic tone. Quinapril and lisinopril produced the most pronounced influence on heart rhythm in anesthetized rats; enalapril was less potent in this respect. In immobilized animals, quinapril and enalapril showed the greatest activity and lisinopril the lowest. The more pronounced effect of quinapril both under anesthesia and during immobilization appears to be linked to the highest affinity of quinaprilat to circulatory and tissue compartments of the renin-angiotensin-aldosterone system.

Impact of angiotensin-converting enzyme inhibition on hemodynamic and autonomic profile of elastase-2 knockout mice

“…This outcome was represented by the power of the LF band ( Figure 3 , Table 1 ), a reliable parameter of sympathetic activity, since blood vessels receive mainly sympathetic innervation. On the other hand, enalapril treatment reduced global HRV in C57BL/6 mice, corroborating previous reports, which stated that both captopril and enalapril can reduce global HRV ( 22 , 23 ). Interestingly, these studies also observed that HR increases after ACE-inhibitor treatment, as seen in ELA-2 KO mice, which is unexpected since human studies suggest that HR is usually not affected with therapeutic doses of captopril ( 24 ).…”

Noninvasive recording of electrocardiogram in conscious rat: A new device

“…[345] In addition, ECG recording of the anesthetized rat lacks validity for HR variability analysis. [67]…”