The multiple indicator dilution technique was employed to examine the in vivo kinetics of oxygen transport in the liver, known for its very permeable capillary bed, and the brain, known for its very tight capillary bed. $ rm sp{18}O sb2$-saturated $ sp{51}$Cr-labeled erythrocytes, labelled albumin, sucrose and water (the tracers for the study substance, vascular, interstitial, and cellular references respectively) were simultaneously injected into the target organs. Timed anaerobic samples were collected at the outflow and analyzed by mass spectrometry for relative $ rm sp{18}O sb2$ enrichment, and for $ gamma$ and $ beta$-radioactivity. Distributed-in-space models of capillary transport were used to analyze the data. / In the liver, oxygen transport and distribution were influenced by the temperature and hematocrit of the perfusate, and shown to be compatible with a flow-limited process. In the brain, flow varied significantly between animals, in concert with parallel changes in oxygen consumption. Analysis indicated that transfer of both $ rm sp{18}O sb2$ and $ sp3$H-water indicators from blood to brain is barrier limited, and it is concluded that low tissue oxygen concentration in the brain is due to limited endothelial permeability to oxygen.
Identifer | oai:union.ndltd.org:LACETR/oai:collectionscanada.gc.ca:QMM.28473 |
Date | January 1994 |
Creators | Kassissia, Ibrahim |
Contributors | Rose, Colin (advisor) |
Publisher | McGill University |
Source Sets | Library and Archives Canada ETDs Repository / Centre d'archives des thèses électroniques de Bibliothèque et Archives Canada |
Language | English |
Detected Language | English |
Type | Electronic Thesis or Dissertation |
Format | application/pdf |
Coverage | Doctor of Philosophy (Division of Experimental Medicine.) |
Rights | All items in eScholarship@McGill are protected by copyright with all rights reserved unless otherwise indicated. |
Relation | alephsysno: 001413316, proquestno: NN00104, Theses scanned by UMI/ProQuest. |
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