Valine oxidation: the synthesis and evaluation of L-[3-3H]valine as a tracer in vivo.

The suitability of L-[3-3H]valine for measuring valine oxidation was studied by comparing its oxidation rate with that of L-[1-14C]valine in rats and pigs. L-[3-3H]valine was synthesized by removal of the tritium on carbon-2 of L-[2,3-3H]valine by acetylation. The acetyl group was removed enzymatically using pig renal acylase 1 (EC 3.

Quantitative partition of threonine oxidation in pigs: effect of dietary threonine.

Kinetic aspects of threonine (Thr) metabolism were examined in eight pigs fed hourly with a diet containing either 0.68% (LT group) or 0.81% (HT group) of Thr (wt/wt), corresponding to 10 and 30% Thr excess, respectively, compared with an "ideal" diet.

Urea synthesis and leucine turnover in growing pigs: changes during 2 d following the addition of carbohydrate or fat to the diet.

1. Studies have been made of the time-sequence of protein metabolic and hormonal changes following an abrupt increase in carbohydrate or fat intake. [3H]leucine and [14C]urea were infused for 72 h, via the aorta, into fourteen female pigs (30-38 kg body-weight).

Effects of the amount and quality of dietary protein on nitrogen metabolism and protein turnover of pigs.

1. The interrelation between protein accretion and whole-body protein turnover were studied by varying the quantity and quality of protein given to growing pigs. 2.