This Article  • References  • Full text PDF  • Reply to article  • Send to a friend  • Save in My Folder  • Save to citation manager  • Permissions  Citing Articles  • Citing articles on HighWire  • Citing articles on Web of Science (16)  • Contact me when this article is cited  Related Content  • Similar articles in this journal  Social Bookmarking   What's this?

II. Normotensive Systemic Hypoxemia

Hart Schutz, MD; Peter R. Silverstein, MD; Matti Vapalahti, MD; Derek A. Bruce, MD; Lena Mela, MD; Thomas W. Langfitt, MD

Arch Neurol. 1973;29(6):417-419.

Abstract
Respiratory function of rabbit brain mitochondria was well maintained after 37 minutes of severe systemic, normotensive hypoxemia. Respiratory control ratios and some state 3 rates were above normal, suggesting "tighter" coupling and lack of respiratory inhibition at cerebral venous oxygen tensions as low as 8 mm Hg and arterial oxygen tensions as low as 11 mm Hg. These findings agree with those of MacMillan and Siesjo, who found no change in the energy charge or nicotinamide adenine nucleotide dehydrogenase: nicotinamide adenine dinucleotide ratio after profound hypoxemia. Conventional concepts of brain tissue oxygenation are challenged by these findings. In addition, evidence supports the experiments of Eklof and Siesjo which show that cerebral venous oxygen tensions are inaccurate in defining tissue oxygenation at low perfusion pressures. Brain mitochondria were "loosely" coupled and inhibited under hypotensive and hypoxemic conditions.

Author Affiliations
Philadelphia

From the Department of Surgery and Division of Neurosurgery, University of Pennsylvania, Philadelphia. Dr. Schutz is now with the Division of Neurosurgery, Toronto Western Hospital; Dr. Silverstein is at Hartford (Conn) Hospital;

Footnotes
Accepted for publication July 3, 1973. and Dr. Vapalahti is with the Neurosurgery Division, University of Turku, Turku, Finland.

Reprint requests to Division of Neurosurgery, Hospital of the University of Pennsylvania, 3400 Spruce St, Philadelphia 19104 (Dr. Langfitt).

CiteULike    Connotea    Del.icio.us    Digg    Reddit    Technorati    Twitter     What's this?

THIS ARTICLE HAS BEEN CITED BY OTHER ARTICLES

The Mitochondrial Permeability Transition Pore and Nitric Oxide Synthase Mediate Early Mitochondrial Depolarization in Astrocytes during Oxygen-Glucose Deprivation
Reichert et al.
J. Neurosci. 2001;21:6608-6616.
ABSTRACT | FULL TEXT