Metabolic alterations in a rat model of hepatic ischaemia reperfusion injury: In vivo hyperpolarized 13 C MRS and metabolic imaging.

ABSTRACT

BACKGROUND & AIMS: Despite a number of studies addressing the pathophysiology of hepatic IRI, a gold standard test for early diagnosis and evaluation of IRI remains elusive. This study investigated the metabolic alterations in a rat model of hepatic IRI using the in vivo hyperpolarized ¹³C MRS and metabolic imaging. METHODS: Hyperpolarized 13 C MRS with IVIM-DWI was performed on the liver of 7 sham-operated control rats and 7 rats before and after hepatic IRI. RESULTS: The hepatic IRI-induced rats showed significantly higher ratios of [1-13 C] alanine/pyruvate, [1-13 C] alanine/tC, [1-13 C] lactate/pyruvate and [1-13 C] lactate/tC compared with both sham-operated controls and rats before IRI, whereas [1-13 C] pyruvate/tC ratio was decreased in IRI-induced rats. In IVIM-DWI study, apparent diffusion coefficient (ADC), f and D values in rats after hepatic IRI were significantly lower than those of rats before IRI and sham-operated controls. The levels of [1-13 C] alanine and [1-13 C] lactate were negatively correlated with ADC, f and D values, whereas the level of [1-13 C] pyruvate was positively correlated with these values. CONCLUSIONS: The levels of [1-13 C] alanine, [1-13 C] lactate and [1-13 C] pyruvate in conjunction with IVIM-DWI will be helpful to evaluate the hepatic IRI as well as these findings can be useful in understanding the biochemical mechanism associated with hepatic damage.