Simon Hu1, Hikari Yoshihara1, Robert Bok1, Peder E. Larson1, John Kurhanewicz1, Daniel B. Vigneron1
1Dept. of Radiology & Biomedical Imaging, University of California at San Francisco, San Francisco, CA, United States
The most commonly used in vivo agent in hyperpolarized 13C metabolic imaging thus far has been [1-13C]pyruvate. In preclinical studies, not only is its uptake detected but also its intracellular enzymatic conversion to metabolic products including [1-13C]lactate. However, the ratio of 13C-lactate/13C-pyruvate measured in this data does not accurately reflect cellular values since much of the [1-13C]pyruvate is extracellular depending on timing, vascular properties and extracellular space and monocarboxylate transporter activity. In order to measure the relative levels of intracellular pyruvate and lactate, in this project we hyperpolarized [1-13C]alanine and monitored the in vivo conversion to [1-13C]pyruvate and [1-13C]lactate.