Hostname: page-component-78c5997874-m6dg7 Total loading time: 0 Render date: 2024-11-08T04:25:06.724Z Has data issue: false hasContentIssue false
  • English
  • Français

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

Published online by Cambridge University Press:  09 March 2007

P. J. Reeds ,
M. F. Fuller ,
A. Cadenhead  and
S. M. Hay
P. J. Reeds
Affiliation:
Rowett Research Institute, Bucksburn, Aberdeen AB2 9SB
M. F. Fuller
Affiliation:
Rowett Research Institute, Bucksburn, Aberdeen AB2 9SB
A. Cadenhead
Affiliation:
Rowett Research Institute, Bucksburn, Aberdeen AB2 9SB
S. M. Hay
Affiliation:
Rowett Research Institute, Bucksburn, Aberdeen AB2 9SB
Rights & Permissions [Opens in a new window]

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

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). At 24 h after the start of the infusion their feed was either changed to one of two isonitrogenous diets containing additional starch (group BS, five animals) or fat (group BF, five animals), or remained unaltered (group BB, four animals). The distribution space of urea was measured by the dilution of a single dose of [14C]urea given both 48 h before and 48 h after the change in diet. The changes in the concentration and specific radioactivity of blood leucine were used to infer changes in protein turnover and those of plasma urea to measure total amino acid catabolism. The concentrations of blood glucose and plasma insulin and cortisol were also measured at approximately two-hourly intervals for the 48 h period following the change in diet.

2. Within 4 h of either change in diet blood leucine concentration was lowered and the leucine specific radioactivity was raised above that in group BB, but after 24 h both the concentration and specific radioactivity of leucine returned to values similar to those in group BB. Eventually the blood leucine specific radioactivity was slightly but not significantly reduced below that of group BB.

3. The addition of starch to the diet significantly reduced the synthesis and concentration of urea within 4 h but, although the addition of fat to the diet eventually lowered the urea concentration and synthesis, both changes were delayed for 18–24 h.

4. In group BS plasma glucose and insulin rose after the addition of starch, but after 24–36 h both returned to values that were the same as those in the animals that received the same diet throughout (group BB). The addition of fat to the diet altered neither blood glucose nor plasma insulin concentrations. The addition of either carbohydrate or fat to the diet eventually reduced pIasma cortisol concentrations, but the change did not occur until 24 h after the change in diet.

5. The results suggest that alterations in non-protein energy supply exert their immediate effect on the degradation of whole-body protein. They do not exclude the possibility that these early changes may reflect opposing changes at different sites. The results also suggest that the rate of urea synthesis may be controlled by the balance between the concentrations of insulin and cortisol, but that under the conditions of these experiments there was little relation between these hormones and the turnover of body protein as measured by the turnover of blood leucine.

Type
General Nutrition papers
Information
British Journal of Nutrition , Volume 58 , Issue 2 , September 1987 , pp. 301 - 311
Copyright
Copyright © The Nutrition Society 1987

References

REFERENCES

Bassett, J. M. & burn, G. D. (1971). Journal of Endocrinology 50, 587–592.CrossRefGoogle Scholar
Bruckental, I., Oldham, J. D. & Sutton, J. D. (1980). British Journal of Nutrition 44, 33–45.CrossRefGoogle Scholar
Buse, M. G. & Reid, S. S. (1975). Journal of Clinical Investigation 56, 1250–1261.Google Scholar
Forbes, E. B., Bratzler, J. W., Thacker, E. J. & Marcy, L. F. (1939). Journal of Nutrition 18, 57–70.CrossRefGoogle Scholar
Fulks, R. M., Li, J. B., & Goldberg, A. L. (1975). Journal of Biological Chemistry 250, 290–298.Google Scholar
Fuller, M. F. & Crofts, R. M. J. (1977). British Journal of Nutrition 38, 479–488.Google Scholar
Fuller, M. F., Weekes, T. E. C., Cadenhead, A. & Bruce, J. B. (1977). British Journal of Nutrition 38, 489–496.Google Scholar
Garlick, P. J., Fern, M. & Preedy, V. R. (1983). Biochemical Journal 210, 669–476.CrossRefGoogle Scholar
Garlick, P. J., Preedy, V. R. & Reeds, P. J. (1985). In Intracellular Protein Catabolism, pp. 555–564 [Khairallah, E. A., Bond, J. S. and Bird, J. W. C., editors]. New York: Allan R. Liss.Google Scholar
Harris, M. M. & Harris, R. G. (1947). Proceedings of the Society of Experimental Biology and Medicine 64, 471–479.Google Scholar
Kotarbinska, M. (1969). Badania nad Przemiana Energii u Rosnacych Swin Wlasne Instytut Zootechniki, Wroctaw, no. 238.Google Scholar
Lotspeich, W. D. (1947). Journal of Biological Chemistry 179, 175–181.CrossRefGoogle Scholar
McNurlan, M. A., Fern, E. B. & Garlick, P. J. (1982). Biochemical Journal 204, 831–838.CrossRefGoogle Scholar
Manchester, K. L. (1970). In Mammalian Protein Metabolism, vol. 4, pp. 229–265 [Munro, H. N., editor]. New York: Academic Press.CrossRefGoogle Scholar
Marsh, W. H., Fingerhut, B. & Miller, H. (1965). Clinical Chemistry 11, 624–629.Google Scholar
Millward, D. J., Odedra, B. & Bates, P. C. (1983). Biochemical Journal 216, 583–589.Google Scholar
Morgan, H. E., Chua, B. H., Fuller, E. O. & Siehl, D. (1980). American Journal of Physiology 238, E431–E439.Google Scholar
Mortimore, G. E. & Poso, A. R. (1984). Federation Proceedings 43, 1289–1294.Google Scholar
Munro, H. N. (1964). In Mammalian Protein Biochemistry, vol. 1, pp. 450–497 [Munro, H. N. and Allison, J. B., editors]. New York: Academic Press.Google Scholar
Nakano, K., Ando, T. & Ashida, K. (1973). Journal of Nutrition 104, 262–269.Google Scholar
Nakano, K. & Ashida, K. (1975). Journal of Nutrition 105, 906–912.Google Scholar
Oddy, V. H. & Lindsay, D. B. (1986). Biochemical Journal 233, 417–425.CrossRefGoogle Scholar
Odedra, B. R., Bates, P. C. & Millward, D. J. (1983). Biochemical Journal 214, 617–627.CrossRefGoogle Scholar
Reeds, P. J. (1972). Effects of insulin and growth hormone on amino acid utilization in muscle. PhD Thesis, University of Southampton.Google Scholar
Reeds, P. J., Cadenhead, A., Fuller, M. F., Lobley, G. E. & McDonald, J. D. (1980). British Journal of Nutrition 43, 445–455.CrossRefGoogle Scholar
Reeds, P. J., Fuller, M. F., Cadenhead, A., Lobley, G. E. & McDonald, J. D. (1981). British Journal of Nutrition 45, 539–546.CrossRefGoogle Scholar
Schwenk, W. F., Tsalikian, E., Beaufree, B. & Haymond, M. W. (1985). American Journal of Physiology 248, E482–E487.Google Scholar
Shipley, R. A. & Clark, R. E. (1972). Tracer Methods For In Vivo Kinetics. New York: Academic Press.Google Scholar
Stewart, P. M. & Walser, M. (1980). Journal of Biological Chemistry 255, 5270–5280.Google Scholar
Tischler, M. E., Desautels, M. & Goldberg, A. L. (1982). Journal of Biological Chemistry 257, 1613–1621.Google Scholar
Tomas, F. M. (1982). Biochemical Journal 208, 593–601.CrossRefGoogle Scholar
Trinder, P. (1969). Annals of Clinical Biochemistry 6, 24–27.Google Scholar
Walser, M. & Stewart, P. M. (1981). Journal of Inherited Metabolic Disease 4, 177–182.Google Scholar
Waterlow, J. C., Millward, D. J. & Garlick, P. J. (1978). Protein Turnover in Mammalian Tissues and in the Whole Body. Amsterdam: North Holland.Google Scholar