Ferdia Aidan Gallagher1,2, Mikko I. Kettunen2,3, De-en Hu2,3, Lorna B. Jarvis4, Rebekah L. McLaughlin2,3, Tim H. Witney2,3, Sam E. Day2,3, Jan H. Ardenkjaer-Larsen5, Ken G. Smith4, Kevin M. Brindle2,3
1Radiology, University of Cambridge, Cambridge, UK; 2CRUK Cambridge Research Institute, Cambridge, UK; 3Biochemistry, University of Cambridge, Cambridge, UK; 4Cambridge Institute for Medical Research, University of Cambridge, Cambridge, UK; 5GE Healthcare, Amersham, UK
Few imaging biomarkers can cross an intact blood-brain barrier. We show here that hyperpolarized 13C-labeled carbon dioxide can be detected within normal mouse brain following the injection of hyperpolarized 13C-labeled bicarbonate. The spatial distribution of the two molecules can also be imaged and the calculated brain pH was shown to be lower than the surrounding tissues, in keeping with previous invasive studies. This method therefore offers the possibility of a new cerebral imaging technique which could be applied to imaging brain function and pathology.