| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH |
|
|
|
|||||||
|
|||||||||
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Articles in PresS, published online ahead of print August 15, 2001
Am J Physiol Renal Physiol, 10.1152/ajprenal.0157.2001
Submitted on May 17, 2001
Accepted on July 24, 2001
1 Smooth Muscle Reseach Group, University of Calgary, Calgary, Alberta, Canada
* To whom correspondence should be addressed. E-mail: rloutzen{at}ucalgary.ca.
ACh induced vasodilation of cortical afferent and efferent arterioles was investigated using the in vitro perfused hydronephrotic rat kidney. ACh reversed angiotensin II induced vasoconstriction in both the afferent and efferent arteriole (106±2% and 75±5% dilation at 10 µmol/L, respectively). Inhibition of nitric oxide synthase (NOS, 100 µmol/L L-NAME) and cyclooxygenase (COX, 10 µmol/L ibuprofen) blocked the sustained ACh response of the afferent arteriole, but did not affect the magnitude of the initial dilation (97±7% dilation). In contrast, NOS/COX inhibition completely abolished ACh-induced efferent arteriolar dilation. The mechanisms underlying the NOS/COX-independent actions of ACh on the afferent arteriole were characterized using K channel blockers. Tetraethylammonium (TEA) had no effect at 1 mmol/L, but attenuated the response at 10 mmol/L (35±5% dilation ). Barium (100 µmol/L) and ouabain (3 mmol/L) had no effect, arguing against a role of the inward rectifier K channel or Na/K ATPase. Charybdotoxin (ChTX, 10 nmol/L) and apamin (1.0 µmol/L) partially blocked the response when administered alone (63±% and 37±5% dilation, respectively) and abolished the response when co-administered (0.1±1.0% dilation). These findings indicate that the NO-independent effects of ACh on the renal microvasculature involve K channels that are sensitive to a combination of apamin and ChTX, but are insensitive to 1 mmol/L TEA or 100 µmol/L barium. This EDHF-like mechanism exerts a segmental-specific action, modulating preglomerular, but not post-glomerular tone, an observation that is consistent with the evolving concept that vasomotor mechanisms in the cortical efferent arteriole do not involve voltage-gated Ca entry.
This article has been cited by other articles:
|
|
 |
|
  G. A. Eppel, D. L. Jacono, M. Shirai, K. Umetani, R. G. Evans, and J. T. Pearson Contrast angiography of the rat renal microcirculation in vivo using synchrotron radiation Am J Physiol Renal Physiol, May 1, 2009; 296(5): F1023 - F1031. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 A. J. Edgley, M. Tare, R. G. Evans, C. Skordilis, and H. C. Parkington In vivo regulation of endothelium-dependent vasodilation in the rat renal circulation and the effect of streptozotocin-induced diabetes Am J Physiol Regulatory Integrative Comp Physiol, September 1, 2008; 295(3): R829 - R839. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 L. Chilton, K. Loutzenhiser, E. Morales, J. Breaks, G. J. Kargacin, and R. Loutzenhiser Inward Rectifier K+ Currents and Kir2.1 Expression in Renal Afferent and Efferent Arterioles J. Am. Soc. Nephrol., January 1, 2008; 19(1): 69 - 76. [Full Text] [PDF]
|
|
|
|
|
|
X. Wang, J. Breaks, K. Loutzenhiser, and R. Loutzenhiser Effects of inhibition of the Na+/K+/2Cl- cotransporter on myogenic and angiotensin II responses of the rat afferent arteriole Am J Physiol Renal Physiol, March 1, 2007; 292(3): F999 - F1006. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 J. Q. Liu, D. Yang, and R. J. Folz A novel bronchial ring bioassay for the evaluation of small airway smooth muscle function in mice Am J Physiol Lung Cell Mol Physiol, August 1, 2006; 291(2): L281 - L288. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
R. Loutzenhiser Inward rectifier currents in pericytes Am J Physiol Regulatory Integrative Comp Physiol, June 1, 2006; 290(6): R1598 - R1600. [Full Text] [PDF]
|
|
|
|
|
|
C. Cao, J. H. Goo, W. Lee-Kwon, and T. L. Pallone Vasa recta pericytes express a strong inward rectifier K+ conductance Am J Physiol Regulatory Integrative Comp Physiol, June 1, 2006; 290(6): R1601 - R1607. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 C. S. Samuel Relaxin: Antifibrotic Properties and Effects in Models of Disease Clin. Med. Res., November 1, 2005; 3(4): 241 - 249. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. D. Imig Epoxide hydrolase and epoxygenase metabolites as therapeutic targets for renal diseases Am J Physiol Renal Physiol, September 1, 2005; 289(3): F496 - F503. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
X. Wang, M. D. Hollenberg, and R. Loutzenhiser Redundant signaling mechanisms contribute to the vasodilatory response of the afferent arteriole to proteinase-activated receptor-2 Am J Physiol Renal Physiol, January 1, 2005; 288(1): F65 - F75. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
Y. Koura, A. Ichihara, Y. Tada, Y. Kaneshiro, H. Okada, C. J. Temm, M. Hayashi, and T. Saruta Anandamide Decreases Glomerular Filtration Rate through Predominant Vasodilation of Efferent Arterioles in Rat Kidneys J. Am. Soc. Nephrol., June 1, 2004; 15(6): 1488 - 1494. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 I. T. Udosen, H. Jiang, H. C. Hercule, and A. O. Oyekan Nitric oxide-epoxygenase interactions and arachidonate-induced dilation of rat renal microvessels Am J Physiol Heart Circ Physiol, November 1, 2003; 285(5): H2054 - H2063. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
X. Wang, G. Trottier, and R. Loutzenhiser Determinants of renal afferent arteriolar actions of bradykinin: evidence that multiple pathways mediate responses attributed to EDHF Am J Physiol Renal Physiol, September 1, 2003; 285(3): F540 - F549. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
H. Nishimura, Y. Yang, C. Hubert, J.-M. Gasc, K. Ruijtenbeek, J. De Mey, H. A. J. S. Boudier, and P. Corvol Maturation-dependent changes of angiotensin receptor expression in fowl Am J Physiol Regulatory Integrative Comp Physiol, July 1, 2003; 285(1): R231 - R242. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. Gschwend, H. Buikema, G. Navis, R. H. Henning, D. de Zeeuw, and R. P. E. van Dokkum Endothelial Dilatory Function Predicts Individual Susceptibility to Renal Damage in the 5/6 Nephrectomized Rat J. Am. Soc. Nephrol., December 1, 2002; 13(12): 2909 - 2915. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. Veerareddy, C.-L. M. Cooke, P. N. Baker, and S. T. Davidge Vascular adaptations to pregnancy in mice: effects on myogenic tone Am J Physiol Heart Circ Physiol, December 1, 2002; 283(6): H2226 - H2233. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
G. Trottier, M. Hollenberg, X. Wang, Y. Gui, K. Loutzenhiser, and R. Loutzenhiser PAR-2 elicits afferent arteriolar vasodilation by NO-dependent and NO-independent actions Am J Physiol Renal Physiol, May 1, 2002; 282(5): F891 - F897. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH |
| Visit Other APS Journals Online |
