17O-MRI of the cerebral metabolic rate of oxygen during electrical stimulation of the paws in the rat at 11.7 T

CMRO2 is an important metric for the evaluation of neurovascular and neurometabolic coupling. However, the degree of coupling between brain activity and CMRO2 remains a matter of debate. In this work, we used 17O-ZTE-MRI at 11.7 T to measure CMRO2 during neuronal activation in the rat primary somatosensory cortex. To improve measurements sensitivity, we acquired data over two consecutive cycles of 17O2 inhalation-washout. We show that a significant functional increase in CMRO2 (+7±5%, p=0.016), and in the rates of metabolized water gain and loss KG (+19±11%, p=0.18) and KL (10±6%, p=0.014) can be detected with good spatial resolution after summation.