title: Two-photon microscopy measurement of cerebral metabolic rate of oxygen using periarteriolar oxygen concentration gradients.
abstract: The cerebral metabolic rate of oxygen ([Formula: see text]) is an essential parameter for evaluating brain function and pathophysiology. However, the currently available approaches for quantifying [Formula: see text] rely on complex multimodal imaging and mathematical modeling. Here, we introduce a method that allows estimation of [Formula: see text] based on a single measurement modality-two-photon imaging of the partial pressure of oxygen ([Formula: see text]) in cortical tissue. We employed two-photon phosphorescence lifetime microscopy (2PLM) and the oxygen-sensitive nanoprobe PtP-C343 to map the tissue [Formula: see text] distribution around cortical penetrating arterioles. [Formula: see text] is subsequently estimated by fitting the changes of tissue [Formula: see text] around arterioles with the Krogh cylinder model of oxygen diffusion. We measured the baseline [Formula: see text] in anesthetized rats and modulated tissue [Formula: see text] levels by manipulating the depth of anesthesia. This method provides [Formula: see text] measurements localized within [Formula: see text] and it may provide oxygen consumption measurements in individual cortical layers or within confined cortical regions, such as in ischemic penumbra and the foci of functional activation.
authors: Massachusetts General Hospital and Harvard Medical School , Optics Division, MGH/HMS/MIT Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, 149 13th Street, Charlestown, Massachusetts 02129, United States.
authors: Sava
authors: S
authors: Sakadžić
authors: Massachusetts General Hospital and Harvard Medical School , Optics Division, MGH/HMS/MIT Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, 149 13th Street, Charlestown, Massachusetts 02129, United States.
authors: Mohammad A
authors: MA
authors: Yaseen
authors: Massachusetts General Hospital and Harvard Medical School , Optics Division, MGH/HMS/MIT Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, 149 13th Street, Charlestown, Massachusetts 02129, United States.
authors: Rajeshwer
authors: R
authors: Jaswal
authors: University of Pennsylvania , Departments of Biochemistry and Biophysics and Chemistry, 422 Curie Boulevard, Philadelphia, Pennsylvania 19104, United States.
authors: Emmanuel
authors: E
authors: Roussakis
authors: University of California San Diego, Department of Neurosciences, 9500 Gilman Drive, La Jolla, California 92093, United States; University of California San Diego, Department of Radiology, 9500 Gilman Drive, La Jolla, California 92093, United States.
authors: Anders M
authors: AM
authors: Dale
authors: University of California San Diego , Department of Radiology, 9500 Gilman Drive, La Jolla, California 92093, United States.
authors: Richard B
authors: RB
authors: Buxton
authors: University of Pennsylvania , Departments of Biochemistry and Biophysics and Chemistry, 422 Curie Boulevard, Philadelphia, Pennsylvania 19104, United States.
authors: Sergei A
authors: SA
authors: Vinogradov
authors: Massachusetts General Hospital and Harvard Medical School , Optics Division, MGH/HMS/MIT Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, 149 13th Street, Charlestown, Massachusetts 02129, United States.
authors: David A
authors: DA
authors: Boas
authors: Massachusetts General Hospital and Harvard Medical School, Optics Division, MGH/HMS/MIT Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, 149 13th Street, Charlestown, Massachusetts 02129, United States; University of California San Diego, Department of Neurosciences, 9500 Gilman Drive, La Jolla, California 92093, United States; University of California San Diego, Department of Radiology, 9500 Gilman Drive, La Jolla, California 92093, United States.
authors: Anna
authors: A
authors: Devor
keywords: cerebral cortex; oxygen metabolism; oxygen partial pressure; phosphorescence; two-photon microscopy