(Hypertension. 1995;25:752-757.)
© 1995 American Heart Association, Inc.
Articles |
Calcium- and Protein Kinase C–Dependent Basal Tone in the Aorta of Hypertensive Rats
From the Department of Pharmacology, New York Medical College, Valhalla.
Abstract We examined the regulatory influence of nitric oxide on development of calcium- and protein kinase C–dependent basal tone in rings of thoracic aortas from rats with aortic coarctation–induced hypertension and from normotensive controls. Aortic rings from hypertensive rats but not those from normotensive rats, bathed in Krebs' bicarbonate buffer and subjected to 2 g of passive stretch, were relaxed by removal of calcium from the buffer and by the protein kinase C inhibitors staurosporine and calphostin C. Protein kinase C activity was much greater in homogenates of aortae from hypertensive rats than in those from normotensive controls (2124±785 versus 608±73 pmol · min-1 · mg protein-1, respectively). Relaxant responses to removal of calcium and to staurosporine were greater in aortic rings rubbed to remove the vascular endothelium than in endothelium-intact rings (-1.07±0.12 versus -0.70±0.10 g tension/mg tissue, respectively, for calcium removal and -1.10±0.12 versus -0.65±0.08 g tension/mg tissue, respectively, for staurosporine). Treatment with an inhibitor of nitric oxide synthesis increased calcium-dependent tone in both intact and endothelium-denuded aortic rings from hypertensive rats. Conversely, the administration of sodium nitroprusside or L-arginine reversed tone in both intact and denuded aortic rings from hypertensive rats, but acetylcholine reversed tone only in intact rings. The relaxant effects of these agents were paralleled by increases in cyclic guanosine monophosphate in aortic tissue. We conclude that aortic rings from rats with aortic coarctation–induced hypertension display calcium-dependent, protein kinase C–mediated tone in the absence of exogenous vasoconstrictors. Furthermore, endogenous nitric oxide from endothelial and nonendothelial sources suppresses the development of this tone.
Key Words: hypertension, arterial • muscle, smooth, vascular • nitric oxide • protein kinase C • calcium • vasoconstriction
This article has been cited by other articles:
 |
|
 |
|
  J.-S. Wang, H. Singh, F. Zhang, T. Ishizuka, H. Deng, R. Kemp, M. S. Wolin, T. H. Hintze, N. G. Abraham, A. Nasjletti, et al. Endothelial Dysfunction and Hypertension in Rats Transduced With CYP4A2 Adenovirus Circ. Res., April 14, 2006; 98(7): 962 - 969. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 Z. Ungvari, A. Csiszar, P. M. Kaminski, M. S. Wolin, and A. Koller Chronic High Pressure-Induced Arterial Oxidative Stress: Involvement of Protein Kinase C-Dependent NAD(P)H Oxidase and Local Renin-Angiotensin System Am. J. Pathol., July 1, 2004; 165(1): 219 - 226. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 E. A. Wehrwein, C. A. Northcott, R. D. Loberg, and S. W. Watts Rho/Rho Kinase and Phosphoinositide 3-Kinase Are Parallel Pathways in the Development of Spontaneous Arterial Tone in Deoxycorticosterone Acetate-Salt Hypertension J. Pharmacol. Exp. Ther., June 1, 2004; 309(3): 1011 - 1019. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
C. A. Northcott, M. N. Poy, S. M. Najjar, and S. W. Watts Phosphoinositide 3-Kinase Mediates Enhanced Spontaneous and Agonist-Induced Contraction in Aorta of Deoxycorticosterone Acetate-Salt Hypertensive Rats Circ. Res., August 23, 2002; 91(4): 360 - 369. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M. Rapacon-Baker, F. Zhang, M. L. Pucci, H. Guan, and A. Nasjletti Expression of myogenic constrictor tone in the aorta of hypertensive rats Am J Physiol Regulatory Integrative Comp Physiol, April 1, 2001; 280(4): R968 - R975. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 K. Yamada, S. N. Iyer, M. C. Chappell, D. Ganten, and C. M. Ferrario Converting Enzyme Determines Plasma Clearance of Angiotensin-(1–7) Hypertension, September 1, 1998; 32(3): 496 - 502. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 C. M. Macica, Y. Yang, K. Lerea, S. C. Hebert, and W. Wang Role of the NH2 terminus of the cloned renal K+ channel, ROMK1, in arachidonic acid-mediated inhibition Am J Physiol Renal Physiol, January 1, 1998; 274(1): F175 - F181. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
A. Dellipizzi, M. L. Pucci, A. Y. Mosny, K. Deseyn, and A. Nasjletti Contribution of Constrictor Prostanoids to the Calcium-Dependent Basal Tone in the Aorta from Rats with Aortic Coarctation-Induced Hypertension: Relationship to Nitric Oxide J. Pharmacol. Exp. Ther., October 1, 1997; 283(1): 75 - 81. [Abstract] [Full Text]
|
|
|
|
|
|
S. d. F. Cortes, V. S. Lemos, and J.-C. Stoclet Alterations in Calcium Stores in Aortic Myocytes From Spontaneously Hypertensive Rats Hypertension, June 1, 1997; 29(6): 1322 - 1328. [Abstract] [Full Text]
|
|
|
|
|
|
H. Guan, V. Cachofeiro, M. L. Pucci, P. M. Kaminski, M. S. Wolin, and A. Nasjletti Nitric Oxide and the Depressor Response to Angiotensin Blockade in Hypertension Hypertension, January 1, 1996; 27(1): 19 - 24. [Abstract] [Full Text]
|
|
|
|
|
|
H. M. Wright and K. U. Malik Prostacyclin Synthesis Elicited by Endothelin-1 in Rat Aorta Is Mediated by an ETA Receptor via Influx of Calcium and Is Independent of Protein Kinase C Hypertension, December 1, 1995; 26(6): 1035 - 1040. [Abstract] [Full Text]
|
|