title: Measurement of cardiac function in conscious rats.
abstract: The goal of this study was to establish that 1. blood velocity profile in the rat aorta is parabolic, and 2. measure of left ventricular thickening fraction can be used in rats. Spontaneously hypertensive and normotensive Wistar Kyoto rats were instrumented with a 20-MHz pulsed Doppler flow probe around the thoracic aorta and a 20-MHz pulsed Doppler thickening probe on the left ventricle. Doppler frequency shifts were measured throughout the entire aorta diameter, and individual blood velocity profiles were constructed. It was demonstrated that blood velocity in the ascending aorta of rats is laminar; therefore, cardiac output can be measured using the pulsed Doppler method. In Wistar Kyoto rats, left ventricular thickening fraction was 24 +/- 1% and 25 +/- 1%, 2 and 3 weeks following surgery. In spontaneously hypertensive rats, left ventricular thickening fraction was 22 +/- 2%. Halothane depressed left ventricular thickening fraction, whereas isoproterenol increased left ventricular thickening fraction in conscious rats. Thus, pulsed Doppler technique is a valuable tool for evaluating cardiovascular function in conscious rats.
authors.affiliation: The University of Texas Medical School at Houston, Department of Anesthesiology, 6431 Fannin, Houston, TX 77030-1503, USA.
authors.forename: M F
authors.initials: MF
authors.lastname: Doursout
authors.forename: P
authors.initials: P
authors.lastname: Wouters
authors.forename: S
authors.initials: S
authors.lastname: Kashimoto
authors.forename: C J
authors.initials: CJ
authors.lastname: Hartley
authors.forename: R
authors.initials: R
authors.lastname: Rabinovitz
authors.forename: J E
authors.initials: JE
authors.lastname: Chelly
mesh_terms: D000704:Analysis of Variance; D018685:Anesthetics, Inhalation / Q000494:pharmacology; D000818:Animals; D001011:Aorta / Q000000981:diagnostic imaging / Q000502:physiology; D001783:Blood Flow Velocity / Q000187:drug effects / Q000502:physiology*; D001794:Blood Pressure / Q000187:drug effects / Q000502:physiology; D002302:Cardiac Output / Q000187:drug effects / Q000502:physiology*; D002316:Cardiotonic Agents / Q000494:pharmacology; D015150:Echocardiography, Doppler; D006221:Halothane / Q000494:pharmacology; D006339:Heart Rate / Q000187:drug effects / Q000502:physiology; D006973:Hypertension / Q000503:physiopathology; D007545:Isoproterenol / Q000494:pharmacology; D008297:Male; D051381:Rats; D017208:Rats, Wistar; D014655:Vascular Resistance / Q000187:drug effects / Q000502:physiology; D016277:Ventricular Function, Left / Q000502:physiology*
chemical_list: D018685:Anesthetics, Inhalation; D002316:Cardiotonic Agents; D007545:Isoproterenol; D006221:Halothane