|
|
||||||||
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
1 Cell Biology and Physiology, University of New Mexico, Albuquerque, NM, USA
* To whom correspondence should be addressed. E-mail: bwalker{at}salud.unm.edu.
Communication between vascular smooth muscle (VSM) cells via low resistance gap junctions may facilitate vascular function by synchronizing the contractile state of individual cells within the vessel wall. We hypothesized that inhibition of gap junctional communication would impair constrictor responses of mesenteric resistance arteries. Immunohistochemical experiments revealed positive staining for connexin 37 (Cx37) in both endothelium and smooth muscle of rat mesenteric arterioles, whereas connexin 43 (Cx43) immunoreactivity was not detected in the mesenteric vasculature. Administration of the gap junction inhibitory peptide Gap 27, which targets Cx37 and Cx43, significantly diminished myogenic vasoconstriction (8.6±3.8% of passive diameter at 100 Torr) and changes in vessel wall [Ca2+]i of mesenteric resistance arteries compared to vessels treated with either vehicle (PSS) (33.5±6.1%) or a control peptide (32.1±6.5%). Administration of 18
-glycyrrhetinic acid (18
-GA), structurally distinct from Gap27, also significantly attenuated myogenic constriction compared to its vehicle control (DMSO) (9.6±3.2% vs. 23.8±4.6%). In contrast, PE-induced vasoconstriction was not altered by gap junction blockers. Attenuated myogenic vasoconstriction resulting from inhibition of gap junctions persisted following disruption of the endothelium. In additional experiments, VSM cell membrane potential (Em) was recorded in mesenteric resistance arteries pressurized to 20 or 100 Torr. VSM Em was depolarized at 100 Torr compared to 20 Torr. However VSM cells in arteries treated with Gap27 were significantly hyperpolarized (-48.6±1.4 mV) at the higher pressure compared to vehicle (-41.4±1.5 mV) and Gap20-treated (-38.4±0.7 mV) vessels. Our findings suggest that inhibition of smooth muscle gap junctions attenuates pressure-induced VSM cell depolarization and myogenic vasoconstriction.
This article has been cited by other articles:
![]() |
D. López, A. Rodríguez-Sinovas, E. Agulló, Án. García, J. A. Sánchez, and D. García-Dorado Replacement of connexin 43 by connexin 32 in a knock-in mice model attenuates aortic endothelium-derived hyperpolarizing factor-mediated relaxation Exp Physiol, October 1, 2009; 94(10): 1088 - 1097. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. Just, L. Kurtz, C. de Wit, C. Wagner, A. Kurtz, and W. J. Arendshorst Connexin 40 Mediates the Tubuloglomerular Feedback Contribution to Renal Blood Flow Autoregulation J. Am. Soc. Nephrol., July 1, 2009; 20(7): 1577 - 1585. [Abstract] [Full Text] [PDF] |
||||
![]() |
E.J. Belin de Chantemele, K. Retailleau, F. Pinaud, E. Vessieres, A. Bocquet, A.L. Guihot, B. Lemaire, V. Domenga, C. Baufreton, L. Loufrani, et al. Notch3 Is a Major Regulator of Vascular Tone in Cerebral and Tail Resistance Arteries Arterioscler Thromb Vasc Biol, December 1, 2008; 28(12): 2216 - 2224. [Abstract] [Full Text] [PDF] |
||||
![]() |
C. M. Sorensen, M. Salomonsson, T. H. Braunstein, M. S. Nielsen, and N.-H. Holstein-Rathlou Connexin mimetic peptides fail to inhibit vascular conducted calcium responses in renal arterioles Am J Physiol Regulatory Integrative Comp Physiol, September 1, 2008; 295(3): R840 - R847. [Abstract] [Full Text] [PDF] |
||||
![]() |
B. R. S. Broughton, B. R. Walker, and T. C. Resta Chronic hypoxia induces Rho kinase-dependent myogenic tone in small pulmonary arteries Am J Physiol Lung Cell Mol Physiol, April 1, 2008; 294(4): L797 - L806. [Abstract] [Full Text] [PDF] |
||||
![]() |
T. Takenaka, T. Inoue, Y. Kanno, H. Okada, C. E. Hill, and H. Suzuki Connexins 37 and 40 transduce purinergic signals mediating renal autoregulation Am J Physiol Regulatory Integrative Comp Physiol, January 1, 2008; 294(1): R1 - R11. [Abstract] [Full Text] [PDF] |
||||
![]() |
O. Platoshyn, Y. Yu, E. A Ko, C. V. Remillard, and J. X.-J. Yuan Heterogeneity of hypoxia-mediated decrease in IK(V) and increase in [Ca2+]cyt in pulmonary artery smooth muscle cells Am J Physiol Lung Cell Mol Physiol, August 1, 2007; 293(2): L402 - L416. [Abstract] [Full Text] [PDF] |
||||
![]() |
R. E. Haddock, T. H. Grayson, T. D. Brackenbury, K. R. Meaney, C. B. Neylon, S. L. Sandow, and C. E. Hill Endothelial coordination of cerebral vasomotion via myoendothelial gap junctions containing connexins 37 and 40 Am J Physiol Heart Circ Physiol, November 1, 2006; 291(5): H2047 - H2056. [Abstract] [Full Text] [PDF] |
||||
![]() |
V. V. Matchkov, A. Rahman, L. M. Bakker, T. M. Griffith, H. Nilsson, and C. Aalkjaer Analysis of effects of connexin-mimetic peptides in rat mesenteric small arteries Am J Physiol Heart Circ Physiol, July 1, 2006; 291(1): H357 - H367. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. Mather, K. A. Dora, S. L. Sandow, P. Winter, and C. J. Garland Rapid Endothelial Cell-Selective Loading of Connexin 40 Antibody Blocks Endothelium-Derived Hyperpolarizing Factor Dilation in Rat Small Mesenteric Arteries Circ. Res., August 19, 2005; 97(4): 399 - 407. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH |
| Visit Other APS Journals Online |