期刊
NEUROIMAGE
卷 42, 期 1, 页码 49-59出版社
ACADEMIC PRESS INC ELSEVIER SCIENCE
DOI: 10.1016/j.neuroimage.2008.04.024
关键词
CBF; CMRO2; oxygen delivery; brain; oxygen transport; microcirculation; fMRI
资金
- NIBIB NIH HHS [R01 EB003375, R01-EB003375] Funding Source: Medline
- NINDS NIH HHS [F32 NS056682-01, F32-NS056682, F32 NS056682] Funding Source: Medline
The dynamics of blood oxygen delivery and tissue consumption produced by evoked stimulation of the rat somato-sensory cortex were investigated. Tissue oxygen tension (P-O2) and laser Doppler flowmetry (LDF) measurements were recorded under two experimental conditions: normal, which represented both oxygen delivery and consumption, and suppressed CBF (achieved using a vasodilator), which only represented tissue oxygen consumption. Forepaw stimulation for 10 s produced increases of 27.7% and 48.8% in tissue P-O2 and LDF signal under normal conditions, respectively. The tissue P-O2 response peaked 9.8 s after stimulation onset and did not show any early transient decreases indicating that measurable oxygen deficits are not required to increase the delivery of oxygen by blood flow. Under suppressed CBF conditions, the LDF signal was mostly suppressed while the tissue P-O2 decreased by 11.7% and reached a minimum 10.8 s after stimulation onset. These data were analyzed using a dynamic model that described the transport of oxygen from blood to tissue. In order to explain the differences between the model prediction of the tissue P-O2 changes and the experimental data, several hypothetical scenarios were considered, such as changes in the vascular volume, perineability-surface area or arterial oxygenation. The increase in tissue P-O2 was found to probably require the recruitment of upstream oxygen from larger arteries as well as increases in the vascular volume at the oxygen exchange sites. The amplitude of the estimated tissue tension of oxygen delivered was about 2.7x larger than the estimated consumption under normal conditions (45.7% vs. 17.1%, respectively). (C) 2008 Elsevier Inc. All rights reserved.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据