Metabolites in the developing rat liver--a proton nuclear magnetic resonance spectroscopic study.

We have used 1H-NMR spectroscopy in vitro to investigate metabolite changes in the rat liver in the first 21 days of life. The principle findings are firstly that betaine, a metabolite of choline, was relatively low (1-2 mumol/g) on days 1-7, then rose sharply to 5-6 mumol/g by day 19, whereas approximately reciprocal changes occurred in taurine levels. Secondly the lactate levels were remarkably low (0.1-0.8 mumol/g) on days 1-7. Changes in two other choline derivatives, phosphocholine (PC) and glycerophosphorylcholine (GPC) are also reported. The results are discussed in the context of the origin of these metabolites in the neonatal period, their levels in the adult (180 day-old) rat and the significance of the measured changes in metabolite levels during liver development.