Published Online
on March 25, 2002

A more recent version of this article appeared on April 9, 2002

This Article Full Text (PDF) All Versions of this Article: 105/14/1713    most recent 01.CIR.0000013783.63773.8Fv1 Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Alert me to new issues of the journal Download to citation manager Request Permissions Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Kobayashi, H. Articles by Takizawa, N. Search for Related Content PubMed Articles by Kobayashi, H. Articles by Takizawa, N. Related Collections Imaging Ischemic biology - basic studies Other Vascular biology

Submitted on December 31, 2001
Accepted on January 31, 2002

Imaging of Oxygen Transfer Among Microvessels of Rat Cremaster Muscle

Hirosuke Kobayashi MD, PhD^* and Naosada Takizawa PhD

From the Department of Medicine (H.K.), School of Medicine, and Information Science Center (N.T.), Kitasato University, Kanagawa, Japan.

^* To whom correspondence should be addressed. E-mail: hiro{at}kitasato-u.ac.jp.

Background—The proximity of capillaries, arterioles, and venules provides complex spatial relationships that lead to oxygen transfer among microvessels. Although a conceptual image of complex oxygen transfer among microvessels has been hypothesized, in vivo mapping of oxygen saturation (SO₂) levels in microvessels had never been performed.

Methods and Results—The oxygen profile of the arterioles and venules of the rat cremaster muscle during normoxia and hypoxia was visualized by preparing pseudo-color images of SO₂ levels based on microspectrophotometry data obtained by using 3 different optical filters and a cooled CCD camera. The SO₂ images showed lower SO₂ levels in arterioles close to their walls, and the SO₂ levels in the paired venules showed higher SO₂ levels close to the arterioles. There were capillaries that crossed the microvessels whose SO₂ levels changed as they crossed the microvessels. The SO₂ levels were lower close to the vessel wall than in the centerline level of the microvessels, and the highest SO₂ levels in venules paralleling arterioles were skewed toward the arterial side. The SO₂ images showed that the SO₂ level in arterioles decreased after crossing venules, whereas the SO₂ level in venules increased after crossing arterioles.

Conclusions—Visualization of intravascular SO₂ levels suggested that oxygen is transferred between paired microvessels and between crossing microvessels in rat cremaster muscle. The possibility that oxygen is transported from some arterioles to venules and tissue through adjacent capillaries is proposed.

Key words: imaging • microcirculation • oxygen • muscles

This article has been cited by other articles:

				R. G. Evans, B. S. Gardiner, D. W. Smith, and P. M. O'Connor Intrarenal oxygenation: unique challenges and the biophysical basis of homeostasis Am J Physiol Renal Physiol, November 1, 2008; 295(5): F1259 - F1270. [Abstract] [Full Text] [PDF]

				A. S. Golub and R. N. Pittman PO2 measurements in the microcirculation using phosphorescence quenching microscopy at high magnification Am J Physiol Heart Circ Physiol, June 1, 2008; 294(6): H2905 - H2916. [Abstract] [Full Text] [PDF]

				X. Chen, D. Jaron, K. A. Barbee, and D. G. Buerk The influence of radial RBC distribution, blood velocity profiles, and glycocalyx on coupled NO/O2 transport J Appl Physiol, February 1, 2006; 100(2): 482 - 492. [Abstract] [Full Text] [PDF]

				M. Shibata, S. Ichioka, and A. Kamiya Estimating oxygen consumption rates of arteriolar walls under physiological conditions in rat skeletal muscle Am J Physiol Heart Circ Physiol, July 1, 2005; 289(1): H295 - H300. [Abstract] [Full Text] [PDF]

				P. C. Johnson, K. Vandegriff, A. G. Tsai, and M. Intaglietta Effect of acute hypoxia on microcirculatory and tissue oxygen levels in rat cremaster muscle J Appl Physiol, April 1, 2005; 98(4): 1177 - 1184. [Abstract] [Full Text] [PDF]