|Yen, Jong Tseng|
Submitted to: Journal of Animal Science Supplement
Publication Type: Abstract Only
Publication Acceptance Date: 12/6/2002
Publication Date: 3/1/2003
Citation: BREGENDAHL, K., LIU, L., FAN, M.Z., BAYLEY, H.S., CANT, J.P., MCBRIDE, B.W., MILLIGAN, L.P., YEN, J. EFFECTS OF AN INTRAPERITONEAL BOLUS INJECTION OF L-PHENYLALANINE ON PHYSIOLOGICAL PARAMETERS IN WEANLING PIGS. JOURNAL OF ANIMAL SCIENCE. 2003. v. 81(Suppl.1): Abstract p. 40. Interpretive Summary:
Technical Abstract: Effects of an intraperitoneal (IP) injection of phenylanine (Phe) on concentrations of free amino acid (AA), glucose, and insulin in plasma, and contents of free AA in tissue homogenates were assessed in pigs. Five blocks of five littermate gilts were weaned at 16 d of age and fed a pelleted starter diet (3340 kcal ME/kg, 1.2% true ileal digestible lysine). On d 8 post-weaning, L-Phe (1.5 mmol/kg body weight) in saline (154 mM) was injected IP according to a randomized complete block design with euthanasia and tissue collection at 15, 30, 45, 60, or 75 min post-injection. Blood samples were collected immediately before Phe injection and euthanasia. Collected tissues were rinsed with ice-cold saline and frozen in liquid nitrogen. Free AA in plasma and tissue homogenates were measured with L norleucine as an internal standard by gas chromatography-mass spectrometry after derivatization with hepta-fluorobutyrate. Plasma Phe increased logarithmically (P<0.05) from 85 to 711 µM (836%) and reached 95% of the maximum concentration 48 min post-injection. Plasma glutamic acid + glutamine, leucine, and lysine concentrations decreased quadratically over time (P<0.05), yet by no more than 28%. Plasma glucose increased from 4.8 mM pre-injection to 5.8 mM 15 min post-injection and returned to pre-injection levels thereafter (cubic effect, P<0.05). The plasma insulin concentration did not change over time (P>0.05). Free Phe contents in cecum, colon, longissimus dorsi, distal small intestine, and stomach increased quadratically over time (P<0.05), but did not change in heart, kidneys, liver, lungs, pancreas, proximal small intestine, and spleen. No changes in tissue free AA other than Phe were observed (P>0.05). In conclusion, Phe injected IP quickly distributes into plasma and tissues with no or little effect on plasma glucose, AA, and insulin concentrations or on tissue free AA contents.