Abstract
This research uses the diastolic decay constant (tau) to investigate the short term mechanism responsible for vasomotor control, mainly the alpha-sympathetic control system. Previous studies have shown that vasomotor control is altered in spontaneously hypertensive rats (SHR) preceding the phase of overt hypertension. The diastolic decay, according to the two element Windkessel model, displays an exponential shape with a decay constant, tau, depending on both the vascular resistance and the compliance. In our experiments, we used tau to characterize vasomotor activity and its control in the normotensive rats as well as in the spontaneously hypertensive rats (SHR) prone to hypertension. The beat to beat value of tau was evaluated from a continuous arterial blood pressure (ABP) signal, measured in the tail artery of the conscious, unrestrained rat. Four months old prehypertensive SHR were compared to their age matched normotensive controls (WKY). To study vasomotor regulation, we computed gains and delay times by investigating the compensatory response in tau to changes in mean ABP (MBP). These parameters are expected in the short term to be neurally controlled by the sympathetic system, mainly alpha-sympathetic. Our set of exper...Continue Reading
References
Jul 1, 1977·Circulation Research·M J Mulvany, W Halpern
Jul 30, 1976·Pflügers Archiv : European journal of physiology·R BusseT Pashch
Aug 1, 1992·Journal of Hypertension. Supplement : Official Journal of the International Society of Hypertension·M F O'Rourke, H R Brunner
Jan 1, 1985·Journal of Cardiovascular Pharmacology·B I LevyM E Safar
Aug 1, 1989·Journal of Cardiovascular Pharmacology·B I LevyM E Safar
Jan 1, 1988·Trends in Pharmacological Sciences·S Akselrod
Dec 1, 1987·Journal of the Autonomic Nervous System·G A Head, R McCarty
Dec 1, 1986·The Journal of Clinical Investigation·C T TingF C Yin
Jan 1, 1980·Clinical and Experimental Hypertension : CHE·F C Reubi, P Weidmann
Jan 1, 1993·Drugs·B Folkow
Feb 1, 1994·Angiology·J K Li, Y Zhu
Nov 6, 1995·Journal of the Autonomic Nervous System·O OzS Akselrod
Jan 1, 1995·Clinical and Experimental Pharmacology & Physiology. Supplement·S EliashS Cohen
Mar 1, 1963·Japanese Circulation Journal·K OKAMOTO, K AOKI