May 1, 1990AJP Heart and Circulatory Physiology
Independent role of arterial O2 tension in local control of coronary blood flow
Key result
Arterial PO2 changes alter coronary blood flow and resistance independently of O2 content or delivery.
Why the study?
The effects of arterial O2 tension on coronary resistance independently of variations in arterial O2 content or myocardial O2 delivery needed to be differentiated.
Population
Blood-perfused isolated rabbit heart preparation
Comparison
High and low arterial PO2 vs normal control PO2 with constant arterial O2 content
Design
Ex vivo experimental animal study
Authors
Discussion
Loading...
Member takes
Implication
Indicates direct PO2 effects on coronary resistance in animals; leaves open translation to human coronary physiology.
Structured PICO
P
Population
Isolated rabbit heart preparation perfused with standard stored human blood to evaluate the effects of arterial O2 tension on coronary blood flow.
I
Intervention
High PO2 (380-389 Torr) and low PO2 (49 Torr) blood perfusion with constant arterial O2 content
C
Comparator
Control PO2 blood perfusion (125-159 Torr)
O
Outcome
Coronary blood flow and coronary resistancesurrogate
Arterial PO2 independently regulates coronary blood flow and resistance, separate from O2 content, O2 delivery, or autonomic nervous system mediation.
Cite This Study
Baron et al. (1990) studied Isolated rabbit heart preparation. Changes in arterial O2 tension (high PO2 and low PO2) vs. Normal PO2 (control) was evaluated on Coronary blood flow (CBF) and coronary resistance. Large changes in arterial O2 tension significantly affected coronary blood flow and resistance independently of the autonomic nervous system, O2 content, or O2 delivery.