Whole‐body recruitment of glycocalyx volume during intravenous adenosine infusion. Issue 5 (11th October 2013)

• Record Type: Journal Article
• Authors: Brands, Judith; van Haare, Judith; Vink, Hans; VanTeeffelen, Jurgen W. G. E.
• Is Part Of: Physiological reports. Volume 1:Issue 5(2013:Oct.)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2013-10-11
• Subjects: Adenosine -- glycocalyx -- indicator dilution -- systemic; Physiology -- Periodicals; 571
• DOI: 10.1002/phy2.102
• Languages: English
• ISSNs: 2051-817X

Abstract

Abstract: Adenosine‐mediated recruitment of microvascular volume in heart and muscle has been suggested to include, in addition to vasodilation of resistance vessels, an increased accessibility of the endothelial glycocalyx for flowing plasma as a result of an impairment of its barrier properties. The aim of the current study was to investigate the effect of systemic intravenous administration of adenosine on the glycocalyx‐dependent exclusion of circulating blood at a whole‐body level. In anesthetized goats ( N = 6), systemic blood‐excluded glycocalyx volume was measured by comparing the intravascular distribution volume of the suggested glycocalyx accessible tracer dextrans with a molecular weight of 40 kDa (Dex‐40) to that of circulating plasma, derived from the dilution of labeled red blood cells and large vessel hematocrit. Systemic glycocalyx volume was determined at baseline and during intravenous infusion of adenosine (157 ± 11.6 μg/kg min −1 ). Blood‐inaccessible glycocalyx volume decreased from 458.1 ± 95.5 to 18.1 ± 62.2 mL ( P < 0.01) during adenosine administration. While circulating plasma volume did not change significantly (617.1 ± 48.5 vs. 759.2 ± 47.9 mL, NS), the decrease in blood‐excluded glycocalyx volume was associated with a decrease in Dex‐40 distribution volume (from 1075.2 ± 71.0 to 777.3 ± 60.0 mL, P < 0.01). Intravenous administration of adenosine is associated with a robust impairment of whole‐body glycocalyx barrier properties, reflected by a greatly reduced exclusion of circulating blood compared to small dextrans. The observed decrease in Dex‐40 distribution volume suggests that the reduction in glycocalyx volume coincides with a reduction in tracer‐accessible vascular volume. Abstract : e00102 Abstract : We demonstrate that intravenous administration of a clinical dose of adenosine in goats greatly decreases blood‐excluded intravascular glycocalyx volume at whole‐body level. During adenosine infusion, the difference between the glycocalyx inaccessible and accessible tracer reduced to nearly zero, illustrating adenosine's potency to robustly increase glycocalyx accessibility for flowing blood. The decrease in blood‐inaccessible glycocalyx volume was associated with an almost equivalent decrease in perfused anatomic vascular volume, reflecting the body's compensation to limit the fall in peripheral resistance during adenosine.