|
|
||||||||
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
NEUROHUMORAL CONTROL OF CARDIOVASCULAR FUNCTION
1Department of Medical Cell Biology, Division of Integrative Physiology, Uppsala University, Uppsala, Sweden; 2Department of Physiology and Pharmacology, Karolinska Institute, Stockholm, Sweden; 3Department of Physiology and Pharmacology, University of Southern Denmark, Odense, Denmark; and 4Department of Physiology, Humboldt University, Berlin, Germany
Submitted 3 May 2005 ; accepted in final form 9 December 2005
The present study was performed to investigate the role of adenosine A1 receptors in regulating blood pressure in conscious mice. Adenosine A1-receptor knockout (A1R/) mice and their wild-type (A1R+/+) littermates were placed on standardized normal-salt (NS), high-salt (HS), or salt-deficient (SD) diets for a minimum of 10 days before telemetric blood pressure and urinary excretion measurements in metabolic cages. On the NS diet, daytime and nighttime mean arterial blood pressure (MAP) was 710 mmHg higher in A1R/ than in A1R+/+ mice. HS diet did not affect the MAP in A1R/ mice, but the daytime and nighttime MAP of the A1R+/+ mice increased by
10 mmHg, to the same level as that in the A1R/. On the SD diet, day- and nighttime MAP decreased by
6 mmHg in both A1R/ and A1R+/+ mice, although the MAP remained higher in A1R/ than in A1R+/+ mice. Although plasma renin levels decreased with increased salt intake in both genotypes, the A1R/ mice had an approximately twofold higher plasma renin concentration on all diets compared with A1R+/+ mice. Sodium excretion was elevated in the A1R/ compared with the A1R+/+ mice on the NS diet. There was no difference in sodium excretion between the two genotypes on the HS diet. Even on the SD diet, A1R/ mice had an increased sodium excretion compared with A1R+/+ mice. An abolished tubuloglomerular feedback response and reduced tubular reabsorption can account for the elevated salt excretion found in A1R/ animals. The elevated plasma renin concentrations found in the A1R/ mice could also result in increased blood pressure. Our results confirm that adenosine, acting through the adenosine A1 receptor, plays an important role in regulating blood pressure, renin release, and sodium excretion.
tubuloglomerular feedback; renal function; telemetry; salt diet
This article has been cited by other articles:
![]() |
D. S. Ponnoth, M. S. Sanjani, C. Ledent, K. Roush, T. Krahn, and S. J. Mustafa Absence of adenosine-mediated aortic relaxation in A2A adenosine receptor knockout mice Am J Physiol Heart Circ Physiol, November 1, 2009; 297(5): H1655 - H1660. [Abstract] [Full Text] [PDF] |
||||
![]() |
J.-N. Yang, J.-F. Chen, and B. B. Fredholm Physiological roles of A1 and A2A adenosine receptors in regulating heart rate, body temperature, and locomotion as revealed using knockout mice and caffeine Am J Physiol Heart Circ Physiol, April 1, 2009; 296(4): H1141 - H1149. [Abstract] [Full Text] [PDF] |
||||
![]() |
T. Rieg and V. Vallon ATP and adenosine in the local regulation of water transport and homeostasis by the kidney Am J Physiol Regulatory Integrative Comp Physiol, February 1, 2009; 296(2): R419 - R427. [Abstract] [Full Text] [PDF] |
||||
![]() |
T. Rieg, K. Pothula, J. Schroth, J. Satriano, H. Osswald, J. Schnermann, P. A. Insel, R. A. Bundey, and V. Vallon Vasopressin regulation of inner medullary collecting ducts and compensatory changes in mice lacking adenosine A1 receptors Am J Physiol Renal Physiol, March 1, 2008; 294(3): F638 - F644. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |