학술논문
In vivo assessment of arterial stiffness in the isoflurane anesthetized spontaneously hypertensive rat
Document Type
Academic Journal
Source
Cardiovascular Ultrasound. September 17, 2014, Vol. 12
Subject
Language
English
Abstract
Author(s): Eric E Morgan[sup.1,5] , Andrew B Casabianca[sup.2] , Samer J Khouri[sup.3] and Andrea L Nestor Kalinoski[sup.4,5] Introduction Decreased arterial elasticity, which results in increased stiffness of the central elastic [...]
Background Rodent models are increasingly used to study the development and progression of arterial stiffness. Both the non-invasive Doppler derived Pulse Wave Velocity (PWV) and the invasively determined arterial elastance index (EaI) have been used to assess arterial stiffness in rats and mice, but the need for anesthetic agents to make these in vivo estimates may limit their utility. Thus, we sought to determine: 1) if known differences in arterial stiffness in spontaneously hypertensive rats (SHR) are detectable by PWV and EaI measurements when made under isoflurane anesthesia, and 2) if these two uniquely acquired assessments of arterial elasticity correlate. Methods We obtained PWV and EaI measurements in isoflurane anesthetized young and old SHRs, which are known to have significant differences in arterial stiffness. Doppler pulse waves were recorded from carotid and iliac arteries and the distance (D) between probe applantation sites was recorded. Simultaneously, an EKG was obtained, and the time intervals between the R-wave of the EKG to the foot of the Doppler waveforms were measured and averaged over three cardiac cycles. Pulse-transit time (T) of the carotid to iliac artery was determined, and PWV was calculated as Distance (D)/Time (T), where D = the distance from the carotid to the iliac notch and T = (R to iliac foot) - (R to carotid foot). EaI was subsequently determined from pressure volumes loops obtained via left ventricle catheterization. Results PWV and EaI were found to be significantly faster in the older rats (13.2 [+ or -] 2.0 vs. 8.0 [+ or -] 0.8 m/sec, p < 0.001; 120 [+ or -] 20 vs. 97 [+ or -] 16 mmHg/[mu]l/g, p Conclusion Our study suggests that isoflurane administration does not limit Doppler PWV or EaI measures in their ability to provide accurate, in vivo assessments of relative arterial stiffness in isoflurane anesthetised SHR rats. Furthermore, PWV data obtained in these rats correlate well with invasively determined EaI. Keywords: Blood pressure, Arterial stiffness, Pulse wave velocity, Arterial elasticity index, Doppler, Ultrasound, Isoflurane, Anesthesia, SHR, Rat
Background Rodent models are increasingly used to study the development and progression of arterial stiffness. Both the non-invasive Doppler derived Pulse Wave Velocity (PWV) and the invasively determined arterial elastance index (EaI) have been used to assess arterial stiffness in rats and mice, but the need for anesthetic agents to make these in vivo estimates may limit their utility. Thus, we sought to determine: 1) if known differences in arterial stiffness in spontaneously hypertensive rats (SHR) are detectable by PWV and EaI measurements when made under isoflurane anesthesia, and 2) if these two uniquely acquired assessments of arterial elasticity correlate. Methods We obtained PWV and EaI measurements in isoflurane anesthetized young and old SHRs, which are known to have significant differences in arterial stiffness. Doppler pulse waves were recorded from carotid and iliac arteries and the distance (D) between probe applantation sites was recorded. Simultaneously, an EKG was obtained, and the time intervals between the R-wave of the EKG to the foot of the Doppler waveforms were measured and averaged over three cardiac cycles. Pulse-transit time (T) of the carotid to iliac artery was determined, and PWV was calculated as Distance (D)/Time (T), where D = the distance from the carotid to the iliac notch and T = (R to iliac foot) - (R to carotid foot). EaI was subsequently determined from pressure volumes loops obtained via left ventricle catheterization. Results PWV and EaI were found to be significantly faster in the older rats (13.2 [+ or -] 2.0 vs. 8.0 [+ or -] 0.8 m/sec, p < 0.001; 120 [+ or -] 20 vs. 97 [+ or -] 16 mmHg/[mu]l/g, p Conclusion Our study suggests that isoflurane administration does not limit Doppler PWV or EaI measures in their ability to provide accurate, in vivo assessments of relative arterial stiffness in isoflurane anesthetised SHR rats. Furthermore, PWV data obtained in these rats correlate well with invasively determined EaI. Keywords: Blood pressure, Arterial stiffness, Pulse wave velocity, Arterial elasticity index, Doppler, Ultrasound, Isoflurane, Anesthesia, SHR, Rat