Biomedical Engineering Reference
In-Depth Information
Chapter 15
Advanced In Vivo Heteronuclear MRS Approaches for
Studying Brain Bioenergetics Driven by Mitochondria
Xiao-Hong Zhu, Fei Du, Nanyin Zhang, Yi Zhang, Hao Lei, Xiaoliang
Zhang, Hongyan Qiao, Kamil Ugurbil and Wei Chen
Abstract
The greatest merit of in vivo magnetic resonance spectroscopy (MRS) methodology used in biomedical
research is its ability for noninvasively measuring a variety of metabolites inside a living organ. It, there-
fore, provides an invaluable tool for determining metabolites, chemical reaction rates and bioenergetics,
as well as their dynamic changes in the human and animal. The capability of in vivo MRS is further
enhanced at higher magnetic fields because of significant gain in detection sensitivity and improvement
in the spectral resolution. Recent progress of in vivo MRS technology has further demonstrated its great
potential in many biomedical research areas, particularly in brain research. Here, we provide a review
of new developments for in vivo heteronuclear
31
Pand
17
O MRS approaches and their applications in
determining the cerebral metabolic rates of oxygen and ATP inside the mitochondria, in both animal and
human brains.
Key words:
In vivo
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P MRS, in vivo
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O MRS, in vivo heteronuclear MRS, brain, magnetic field,
cerebral bioenergetics, brain metabolism, brain function, MRI.
1. Introduction
1.1. Cerebral
Bioenergetics and
Brain Function
The brain is an extraordinary organ; with its unique structure
and complex functions, it distinguishes itself from other organs
in many aspects. Unlike cardiac and skeletal muscles, the brain
does not perform mechanical work. The major cellular func-
tions in the brain include excitation and conduction resulting
in unceasing electrophysiological activities in normal brain, even
at rest. These integrated neuronal activities are essential for per-
forming brain functions. Nevertheless, to sustain these activities
