| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH |
|
|
|
|||||||
|
|||||||||
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
1 Department of Physiology, Tulane University Health Sciences Center, New Orleans, LA, USA
* To whom correspondence should be addressed. E-mail: majid{at}tulane.edu.
To assess the role of superoxide (O2-) and nitric oxide (NO) interaction in mediating the renal actions of angiotensin II (Ang II), we examined the renal responses to intraarterial infusion of Ang II (0.5 ng.kg-1.min-1) before and during administration of a superoxide dismutase mimetic, tempol (0.5 mg.kg-1.min-1) in the presence or absence of NO synthase inhibitor, nitro-L-arginine (NLA; 50 µg.kg-1.min-1) in anesthetized dogs pretreated with enalaprilat (33 µg.kg-1.min-1). In one group of dogs (n=7), Ang II infusion prior to tempol infusion caused decreases of 24± 4% in renal blood flow (RBF), 55±7% in urine flow (V) and 53±8% in UNaV with a slight decrease in glomerular filtration rate (GFR; -7.8±3.4%). Tempol infusion alone did not cause significant alterations in RBF, GFR, V or UNaV; however, Ang II in the presence of tempol caused a smaller degree of decreases in RBF (-12±2%), in V (-16± 5%) and in UNaV (-27±10%) with a slight increase in GFR (6.6± 2.8%) than the responses observed prior to tempol. In another group of NLA treated dogs (n=6), tempol infusion also caused significant attenuation in the Ang II induced responses on RBF (-13±3% vs -22 ±7%), GFR (-19± 5% vs -33±3), V (-15±12% vs -28±4%) and UNaV (-11±14% vs -32±7%). These data demonstrate that renal responses to AngII are partly mediated by O2- generation and its interaction with NO. The sodium retaining effect of AngII is greatly influenced by O2- generation, particularly in the condition of NO deficiency.
This article has been cited by other articles:
|
|
 |
|
  C. S. Wilcox and A. Pearlman Chemistry and Antihypertensive Effects of Tempol and Other Nitroxides Pharmacol. Rev., December 1, 2008; 60(4): 418 - 469. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M. Z. Haque and D. S. A. Majid Reduced renal responses to nitric oxide synthase inhibition in mice lacking the gene for gp91phox subunit of NAD(P)H oxidase Am J Physiol Renal Physiol, September 1, 2008; 295(3): F758 - F764. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
A. Just, C. L. Whitten, and W. J. Arendshorst Reactive oxygen species participate in acute renal vasoconstrictor responses induced by ETA and ETB receptors Am J Physiol Renal Physiol, April 1, 2008; 294(4): F719 - F728. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 A. Just, A. J. M. Olson, C. L. Whitten, and W. J. Arendshorst Superoxide mediates acute renal vasoconstriction produced by angiotensin II and catecholamines by a mechanism independent of nitric oxide Am J Physiol Heart Circ Physiol, January 1, 2007; 292(1): H83 - H92. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 U. K. Dutta, J. Lane, L. J. Roberts II, and D. S. A. Majid Superoxide formation and interaction with nitric oxide modulate systemic arterial pressure and renal function in salt-depleted dogs. Experimental Biology and Medicine, March 1, 2006; 231(3): 269 - 276. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 L. Kopkan and D. S.A. Majid Enhanced Superoxide Activity Modulates Renal Function in NO-Deficient Hypertensive Rats Hypertension, March 1, 2006; 47(3): 568 - 572. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
L. Kopkan, A. Castillo, L. G. Navar, and D. S. A. Majid Enhanced superoxide generation modulates renal function in ANG II-induced hypertensive rats Am J Physiol Renal Physiol, January 1, 2006; 290(1): F80 - F86. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. K. Fellner and W. J. Arendshorst Angiotensin II, reactive oxygen species, and Ca2+ signaling in afferent arterioles Am J Physiol Renal Physiol, November 1, 2005; 289(5): F1012 - F1019. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 C. S. Wilcox Oxidative stress and nitric oxide deficiency in the kidney: a critical link to hypertension? Am J Physiol Regulatory Integrative Comp Physiol, October 1, 2005; 289(4): R913 - R935. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
L. Kopkan and D. S. A. Majid Superoxide Contributes to Development of Salt Sensitivity and Hypertension Induced by Nitric Oxide Deficiency Hypertension, October 1, 2005; 46(4): 1026 - 1031. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH |
| Visit Other APS Journals Online |
