Articles |
the Department of Medical Physics, Academic Medical Center, University of Amsterdam (The Netherlands).
Intramyocardial pressure becomes high in systole and decreases in diastole. Therefore, the transmural pressure of the intramyocardial vessels is pulsatile, resulting in the cyclic distension of these vessels. However, the effect of pulsatility on the behavior of the coronary resistance vessels has not been evaluated. To assess the influence of pulsatile pressure on the behavior of the coronary arterioles, we measured the luminal cross-sectional area (CSA) of coronary arterioles under cyclically changing transmural pressure. Isolated porcine coronary arterioles (internal diameter, 100 to 150 µm) were cannulated with two micropipettes and pressurized with square waves (1 Hz) through both pipettes so as not to induce flow-dependent vasodilation. During the presence (active, induced by acetylcholine; n=7) or absence (passive, abolished by bradykinin; n=7) of vascular tone, the CSA was measured under the following conditions: (1) The amplitude of the pressure pulse was changed at a fixed mean pressure. (2) The mean pressure was changed at a fixed pressure pulse. With increasing pulse pressure, the mean CSA at steady state increased under active conditions, whereas it decreased under passive conditions (P<.0001). This vasodilatory effect of pulse pressure remained present after endothelial denudation (P<.0001; n=6 vessels with basal tone, n=9 vessels with U46619-induced tone). The mean steady state CSA under passive conditions increased with the mean pressure (P<.05), whereas under active conditions it remained constant in the range of mean pressures between 50 and 100 mm Hg, reflecting myogenic responsiveness. These results indicate that an increase in amplitude of the pressure pulse dilates coronary arterioles. The vasodilating effect of the pulsation may compensate partly for the extra compressing effect of cardiac contraction on the intramyocardial vessels.
Key Words: coronary arteriole myogenic response pulsatile pressure isolated vessel
This article has been cited by other articles:
![]() |
G. S. Kassab, M. Kostelec, G. D. Buckberg, J. Covell, A. Sadeghi, and J. I.E. Hoffman Myocardial protection in the failing heart: II. Effect of pulsatile cardioplegic perfusion under simulated left ventricular restoration J. Thorac. Cardiovasc. Surg., October 1, 2006; 132(4): 884 - 890. [Abstract] [Full Text] [PDF] |
||||
![]() |
N. Westerhof, C. Boer, R. R. Lamberts, and P. Sipkema Cross-talk between cardiac muscle and coronary vasculature. Physiol Rev, October 1, 2006; 86(4): 1263 - 1308. [Abstract] [Full Text] [PDF] |
||||
![]() |
O. Sorop, E. N. T. P. Bakker, A. Pistea, J. A. E. Spaan, and E. VanBavel Calcium channel blockade prevents pressure-dependent inward remodeling in isolated subendocardial resistance vessels Am J Physiol Heart Circ Physiol, September 1, 2006; 291(3): H1236 - H1245. [Abstract] [Full Text] [PDF] |
||||
![]() |
D. Sun, A. Huang, and G. Kaley Mechanical compression elicits NO-dependent increases in coronary flow Am J Physiol Heart Circ Physiol, December 1, 2004; 287(6): H2454 - H2460. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. J. M. Cornelissen, J. Dankelman, E. VanBavel, and J. A. E. Spaan Balance between myogenic, flow-dependent, and metabolic flow control in coronary arterial tree: a model study Am J Physiol Heart Circ Physiol, June 1, 2002; 282(6): H2224 - H2237. [Abstract] [Full Text] [PDF] |
||||
![]() |
O. Sorop, J. A. E. Spaan, and E. VanBavel Pulsation-induced dilation of subendocardial and subepicardial arterioles: effect on vasodilator sensitivity Am J Physiol Heart Circ Physiol, January 1, 2002; 282(1): H311 - H319. [Abstract] [Full Text] [PDF] |
||||
![]() |
T. Nakano, R. Tominaga, S. Morita, M. Masuda, I. Nagano, K.-i. Imasaka, and H. Yasui Impacts of pulsatile systemic circulation on endothelium-derived nitric oxide release in anesthetized dogs Ann. Thorac. Surg., July 1, 2001; 72(1): 156 - 162. [Abstract] [Full Text] [PDF] |
||||
![]() |
D. Merkus, I. Vergroesen, O. Hiramatsu, H. Tachibana, H. Nakamoto, E. Toyota, M. Goto, Y. Ogasawara, J. A. E. Spaan, and F. Kajiya Stenosis differentially affects subendocardial and subepicardial arterioles in vivo Am J Physiol Heart Circ Physiol, April 1, 2001; 280(4): H1674 - H1682. [Abstract] [Full Text] [PDF] |
||||
![]() |
N. Paolocci, P. Pagliaro, T. Isoda, F. W. Saavedra, and D. A. Kass Role of Calcium-Sensitive K+ Channels and Nitric Oxide in In Vivo Coronary Vasodilation From Enhanced Perfusion Pulsatility Circulation, January 2, 2001; 103(1): 119 - 124. [Abstract] [Full Text] [PDF] |
||||
![]() |
C. D. Figueroa, A. Marchant, U. Novoa, U. Forstermann, K. Jarnagin, B. Scholkens, and W. Muller-Esterl Differential Distribution of Bradykinin B2 Receptors in the Rat and Human Cardiovascular System Hypertension, January 1, 2001; 37(1): 110 - 120. [Abstract] [Full Text] [PDF] |
||||
![]() |
T. Nakano, R. Tominaga, I. Nagano, H. Okabe, and H. Yasui Pulsatile flow enhances endothelium-derived nitric oxide release in the peripheral vasculature Am J Physiol Heart Circ Physiol, April 1, 2000; 278(4): H1098 - H1104. [Abstract] [Full Text] [PDF] |
||||
![]() |
P. Pagliaro, N. Paolocci, T. Isoda, W. F Saavedra, G. Sunagawa, and D. A Kass Reversal of glibenclamide-induced coronary vasoconstriction by enhanced perfusion pulsatility: possible role for nitric oxide Cardiovasc Res, March 1, 2000; 45(4): 1001 - 1009. [Abstract] [Full Text] [PDF] |
||||
![]() |
P. Pagliaro, H. Senzaki, N. Paolocci, T. Isoda, G. Sunagawa, F. A Recchia, and D. A Kass Specificity of synergistic coronary flow enhancement by adenosine and pulsatile perfusion in the dog J. Physiol., October 1, 1999; 520(1): 271 - 280. [Abstract] [Full Text] [PDF] |
||||
![]() |
E. Toyota, M. Goto, H. Nakamoto, J. Ebata, H. Tachibana, O. Hiramatsu, Y. Ogasawara, and F. Kajiya Endothelium-derived nitric oxide enhances the effect of intraaortic balloon pumping on diastolic coronary flow Ann. Thorac. Surg., May 1, 1999; 67(5): 1254 - 1261. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. J. Davis and M. A. Hill Signaling Mechanisms Underlying the Vascular Myogenic Response Physiol Rev, April 1, 1999; 79(2): 387 - 423. [Abstract] [Full Text] [PDF] |
||||
![]() |
E. VanBavel, J. P. M. Wesselman, and J. A. E. Spaan Myogenic Activation and Calcium Sensitivity of Cannulated Rat Mesenteric Small Arteries Circ. Res., February 9, 1998; 82(2): 210 - 220. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. J. M. Cornelissen, J. Dankelman, E. VanBavel, and J. A. E. Spaan Balance between myogenic, flow-dependent, and metabolic flow control in coronary arterial tree: a model study Am J Physiol Heart Circ Physiol, June 1, 2002; 282(6): H2224 - H2237. [Abstract] [Full Text] [PDF] |
||||
|
Circulation Research Home | Subscriptions | Archives | Feedback | Authors | Help | AHA Journals Home | Search Copyright © 1996 American Heart Association, Inc. All rights reserved. Unauthorized use prohibited. |