The effect of glucose infusion on the plasma free amino acids in sheep.
1. Glucose in solution in saline, or saline alone, was administered to a group of twenty ewes during late pregnancy and again after lambing. Sequential blood samples were taken before and after the infusion and the concentration of plasma free amino acids was determined. 2. The effect of glucose was to reduce the concentrations of all amino acids except alanine. The reduction was greatest for tryptophan in the pregnant sheep, but this amino acid showed no significant change in the lactating animals. 3. An attempt to rank the amino acids on the basis of their response to glucose infusion indicated  that, with the exception of tryptophan for the preparturient ewes, groups of essential amino acids could not be distinguished from each other. These groups were, for the preparturient sheep, valine, leucine, phenylalanine and isoleucine, and for the postparturient animals, isoleucine, lysine, methionine, valine and phenylalanine.
D000596:Amino Acids / Q000097:blood*; D000601:Amino Acids, Essential / Q000097:blood; D000824:Animal Nutritional Physiological Phenomena; D000818:Animals; D005260:Female; D005947:Glucose / Q000008:administration & dosage / Q000494:pharmacology*; D007263:Infusions, Parenteral; D007532:Isoleucine / Q000097:blood; D007774:Lactation; D007930:Leucine / Q000097:blood; D008239:Lysine / Q000097:blood; D008715:Methionine / Q000097:blood; D009751:Nutritional Requirements; D010649:Phenylalanine / Q000097:blood; D011247:Pregnancy; D011270:Pregnancy, Animal; D012756:Sheep / Q000097:blood*; D014633:Valine / Q000097:blood
D000596:Amino Acids; D000601:Amino Acids, Essential; D007532:Isoleucine; D010649:Phenylalanine; D008715:Methionine; D007930:Leucine; D014633:Valine; D005947:Glucose; D008239:Lysine