In rat heart arteries, a ketone body relaxed the blood vessels starting at low concentrations, with the strongest effect at higher doses.
Scientific Claim
In isolated rat coronary arteries pre-contracted with U46619, sodium 3-hydroxybutyrate caused concentration-dependent vasorelaxation starting at 1–3 mM, with an EC50 of 12.4 mM and up to 60% relaxation at higher concentrations.
Original Statement
“3-OHB caused concentration-dependent vasorelaxation of coronary septal arteries beginning at concentrations above 1 mM and with an EC50 value of 12.4 mM (Fig. 3A, B). In the physiologically relevant concentration range between 2 and 4 mM, the coronary vasorelaxation to 3-OHB (Fig. 3B) was 20–25% of that to 5 µM of the classical endothelium-dependent vasorelaxant acetylcholine (Fig. 3E).”
Evidence Quality Assessment
Claim Status
appropriately stated
Study Design Support
Design supports claim
Appropriate Language Strength
definitive
Can make definitive causal claims
Assessment Explanation
The controlled ex vivo experiments with precise concentration measurements support definitive quantitative statements for the model.
Evidence from Studies
Supporting (1)
Ketone body 3-hydroxybutyrate elevates cardiac output through peripheral vasorelaxation and enhanced cardiac contractility