Table 1.

Factors that may influence BOLD MR measures

Factors affecting oxygen delivery	Factors affecting oxygen consumption (tubular transport)
Renal blood flow (stenosis)	Water balance
Renal perfusion (vascular density)	Sodium balance
Arteriovenous O2 shunting	Diuretics
Anemia	Prostaglandin inhibitors
Oxygen/hemoglobin dissociation curve (pH?, temperature?)	Iodinated contrast Angiotensin-converting enzyme inhibitors/angiotensin receptor blockers Antioxidants?

Abbreviation: BOLD MR, blood oxygen level-dependent magnetic resonance.