Significance of the Bohr effect for tissue oxygenation in a model with counter-current blood flow

Respiration Physiology
H KobayashiP Scheid

Abstract

Counter-current arrangement of afferent and efferent blood flow in tissues is commonly considered to be detrimental to tissue oxygenation, since O2 diffusion would shunt O2 away from the tissue. We have investigated the combined effects of counter-current CO2 and O2 exchange in a simple model, paying particular attention to the Bohr effect. We have obtained the following main results. (1) Back-diffusion of CO2 leads to increasing CO2 partial pressure (PCO2) and CO2 content along the afferent vessel. This is enhanced when fixed acid is released by the tissue into the venous blood, e.g. during hypoxia, which leads to a further PCO2 increase therein. (2) The increasing PCO2, with concomitant decrease in pH, in the afferent blood leads to a decrease in blood O2 affinity (Bohr effect) and thus results in increased PO2. (3) The resulting O2 diffusion shunt diminishes the O2 content in afferent blood, but for most conditions its PO2 remains higher than without the Bohr effect. (4) During hypoxia, both the PO2 in blood reaching the tissue (Pta) as well as in that leaving it (Ptv) are significantly elevated above the level without the Bohr effect. Moreover, with fixed acid release both Pta and Ptv for O2 can be higher than the arterial ...Continue Reading

References

Sep 9, 1975·Pflügers Archiv : European journal of physiology·T KawashiroP Scheid
Jan 1, 1977·International Anesthesiology Clinics·P D Wagner
Jan 1, 1984·Advances in Experimental Medicine and Biology·J PiiperP Scheid
Oct 1, 1984·Circulation Research·R M EffrosP Silverman

❮ Previous
Next ❯

Citations

Mar 1, 1990·Respiration Physiology·H KobayashiP Scheid
Aug 1, 1991·Respiration Physiology·D BöningS Göke
Jan 1, 2012·Annals of Vascular Diseases·Fumitaka IkomiToshio Ohhashi
Sep 1, 1993·Journal of Cerebral Blood Flow and Metabolism : Official Journal of the International Society of Cerebral Blood Flow and Metabolism·R S SchacterleJ M Adams
Mar 5, 2010·American Journal of Physiology. Renal Physiology·Roger G EvansPaul M O'Connor
Mar 4, 2011·American Journal of Physiology. Renal Physiology·Bruce S GardinerRoger G Evans
Mar 22, 2003·American Journal of Physiology. Heart and Circulatory Physiology·John A RussellTimothy I Musch
Jul 5, 2003·Physiological Reviews·Amy G TsaiMarcos Intaglietta
Jun 19, 2002·Journal of Applied Physiology·Crystal M GeerDavid C Poole

❮ Previous
Next ❯

Related Concepts

Trending Feeds

COVID-19

Coronaviruses encompass a large family of viruses that cause the common cold as well as more serious diseases, such as the ongoing outbreak of coronavirus disease 2019 (COVID-19; formally known as 2019-nCoV). Coronaviruses can spread from animals to humans; symptoms include fever, cough, shortness of breath, and breathing difficulties; in more severe cases, infection can lead to death. This feed covers recent research on COVID-19.

Blastomycosis

Blastomycosis fungal infections spread through inhaling Blastomyces dermatitidis spores. Discover the latest research on blastomycosis fungal infections here.

Nuclear Pore Complex in ALS/FTD

Alterations in nucleocytoplasmic transport, controlled by the nuclear pore complex, may be involved in the pathomechanism underlying multiple neurodegenerative diseases including Amyotrophic Lateral Sclerosis and Frontotemporal Dementia. Here is the latest research on the nuclear pore complex in ALS and FTD.

Applications of Molecular Barcoding

The concept of molecular barcoding is that each original DNA or RNA molecule is attached to a unique sequence barcode. Sequence reads having different barcodes represent different original molecules, while sequence reads having the same barcode are results of PCR duplication from one original molecule. Discover the latest research on molecular barcoding here.

Chronic Fatigue Syndrome

Chronic fatigue syndrome is a disease characterized by unexplained disabling fatigue; the pathology of which is incompletely understood. Discover the latest research on chronic fatigue syndrome here.

Evolution of Pluripotency

Pluripotency refers to the ability of a cell to develop into three primary germ cell layers of the embryo. This feed focuses on the mechanisms that underlie the evolution of pluripotency. Here is the latest research.

Position Effect Variegation

Position Effect Variagation occurs when a gene is inactivated due to its positioning near heterochromatic regions within a chromosome. Discover the latest research on Position Effect Variagation here.

STING Receptor Agonists

Stimulator of IFN genes (STING) are a group of transmembrane proteins that are involved in the induction of type I interferon that is important in the innate immune response. The stimulation of STING has been an active area of research in the treatment of cancer and infectious diseases. Here is the latest research on STING receptor agonists.

Microbicide

Microbicides are products that can be applied to vaginal or rectal mucosal surfaces with the goal of preventing, or at least significantly reducing, the transmission of sexually transmitted infections. Here is the latest research on microbicides.