Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2009 Jan-Feb;61(1):183-90.
doi: 10.1016/s1734-1140(09)70020-9.

Rabbit erythrocytes release ATP and dilate skeletal muscle arterioles in the presence of reduced oxygen tension

Randy S Sprague  1 , Madelyn S Hanson, David Achilleus, Elizabeth A Bowles, Alan H Stephenson, Meera Sridharan, Shaquria Adderley, Jesse Procknow, Mary L Ellsworth
Affiliations

Rabbit erythrocytes release ATP and dilate skeletal muscle arterioles in the presence of reduced oxygen tension

Randy S Sprague et al. Pharmacol Rep. 2009 Jan-Feb.

Abstract

In skeletal muscle, oxygen (O(2)) delivery to appropriately meet metabolic need requires mechanisms for detection of the magnitude of O(2) demand and the regulation of O(2) delivery. Erythrocytes, when exposed to a decrease in O(2) tension, release both O(2) and the vasodilator adenosine triphosphate (ATP). The aims of this study were to establish that erythrocytes release ATP in response to reduced O(2) tension and determine if erythrocytes are necessary for the dilation of isolated skeletal muscle arterioles exposed to reduced extraluminal O(2) tension. Rabbit erythrocytes exposed to reduced O(2) tension in a tonometer (n = 5, pO(2) = 27 +/- 3, p < 0.01) released ATP in response to reduced O(2) tension. ATP release increased in proportion to the decrease in O(2) tension. The contribution of erythrocytes to the response of skeletal muscle arterioles to reduced extraluminal O(2) tension was determined using isolated hamster cheek pouch retractor muscle arterioles perfused with buffer (n = 11, mean diameter 52 +/- 3 mum) in the absence and presence of rabbit erythrocytes. Without erythrocytes, arterioles did not dilate when exposed to reduced extraluminal O(2) tension (pO(2) = 32 +/- 4 mmHg). In contrast, when rabbit erythrocytes were present in the perfusate (hematocrit 15%), the same decrease in O(2) tension resulted in a 20 +/- 4% dilation (p < 0.01). These results provide support for the hypothesis that erythrocytes, via their ability to release O(2) along with ATP in response to exposure to reduced O(2) tension, can participate in the matching of O(2) delivery with metabolic need in skeletal muscle.

PubMed Disclaimer

Figures

Figure 1
Figure 1
Effect of exposure of washed rabbit erythrocytes (20% hematocrit, n=5) to gas mixtures containing either 15% O2, 6% CO2, balance N2 (NORMOXIA) or 0% O2, 6% CO2, balance N2 (REDUCED O2) on oxygen tension (panel A) and ATP release (panel B). † = p< 0.01 compared to NORMOXIA. Values are mean ± SE.
Figure 2
Figure 2
Linear regression relationship between the change (decrease) in O2 tension (pO2) and the change (increase) in ATP release from rabbit erythrocytes in response to exposure to reduced O2 (p<0.02).
Figure 3
Figure 3
Panel A: Buffer PO2 in the isolated vessel chamber when equilibrated with either room air (NORMOXIA) or 100% N2 (REDUCED O2) (n=11). † = p< 0.01 compared to NORMOXIA. Values are mean ± SE. Panel B: Percent change in vessel diameter in response to exposure to reduced O2 tension in the absence (BUFFER) and presence of rabbit erythrocytes (BUFFER + RBCs, hematocrit 15%) (n=11). † = p< 0.01 compared to diameter during normoxia. Values are mean ± SE.
See this image and copyright information in PMC

References

    1. Bergfeld GR, Forrester T. Release of ATP from human erythrocytes in response to a brief period of hypoxia and hypercapnea. Cardiovasc Res. 1992;26:40–47. - PubMed
    1. Brown IP, Thompson CI, Belloni FL. Mechanisms of coronary vasodilation produced by ATP in guinea-pig isolated perfused heart. Br J Pharmacol. 1992;105:211–215. - PMC - PubMed
    1. Collins DM, McCullough WT, Ellsworth ML. Conducted vascular responses: Communication across the capillary bed. Microvas Res. 1998;56:43–53. - PubMed
    1. Communi D, Raspe E, Pirotton S, Boeynaems JM. Coexpression of P2y and P2u receptors on aortic endothelial cells: Comparison of cell localization and signaling pathways. Circ Res. 1991;76:191–198. - PubMed
    1. Dazel HH, Westfall DP. Receptors for adenine nucleotides and nucleosides: Subclassification, distribution and molecular characterization. Pharmacological Reviews. 1994;46:449–466. - PubMed

Publication types