[Effect of glutamic acid content in the diet on the catabolic rate of the isotope-labeled glutamic acid in rats. 4. Measurement of 14C-glutamic acid oxidation to 14CO2 with various energy sources in the diet].
48 male rats (body weight 80-100 g) were fed with 2 diets different in the glutamic acid content (diet I 2.42 and diet II 6.24% glutamic acid in the dry matter). The mixture of the other synthetic L-amino acids was adapted to the egg protein pattern corresponding 10% crude protein in the diet. Each diet was fed either on 73% or 98 to 104% of the energy maintenance requirement. After 7 days of experimental feeding 14C-U-L-glutamic acid was given to each group by intragastric infusion (i.g.), intraperitoneal (i.p.) or subcutaneous injection (s.c.), respectively, followed by a measurement of the CO2-and 14CO2-excretion during two subsequent periods of 3 hours. The CO2-excretion was lower in animals with restricted energy intake especially during the first 3 hour-period, which was started 2 hours after feed intake. The relative 14CO2-excretion (percent of the dose) was neither significantly influenced by the level of energy intake nor by the amount of dietary glutamic acid. The highest degradation rates of 14C-glutamic acid to 14CO2 were measured after i.g. application (more than 50%), followed by the i.p. injection (nearly 50%) and the lowest values were observed after s.c. injection (about 40%). These differences were only evident during the first CO2-absorption period. Furthermore the s.c. injection caused a lower specific radioactivity of CO2 compared with the data after i.g. and i.p. application. The results suggest the high metabolic activity of the intestinal tissue for glutamic acid.
Wilke
A
A
Bergner
H
H
Simon
O
O
D000821:Animal Feed / Q000032:analysis; D000818:Animals; D001835:Body Weight; D002245:Carbon Dioxide / Q000378:metabolism*; D002250:Carbon Radioisotopes; D004734:Energy Metabolism; D005971:Glutamates / Q000008:administration & dosage / Q000032:analysis / Q000378:metabolism*; D018698:Glutamic Acid; D008297:Male; D010084:Oxidation-Reduction; D051381:Rats / Q000378:metabolism*
D002250:Carbon Radioisotopes; D005971:Glutamates; D002245:Carbon Dioxide; D018698:Glutamic Acid
Der Einfluss des Glutaminsäuregehaltes der Diät auf die Katabolisierung von isotopenmarkierter Glutaminsäure bei Ratten. 4. Mitteilung Messung der Oxydation von 14C-Glutaminsäure zu 14CO2 bei unterschiedlicher Energieversorgung über die Diät.