Hostname: page-component-848d4c4894-v5vhk Total loading time: 0 Render date: 2024-06-20T18:34:04.819Z Has data issue: false hasContentIssue false

Characteristics of α–aminoisobutyric acid transport by lactating rat mammary gland

Published online by Cambridge University Press:  01 June 2009

D. B. Shennan
Affiliation:
Hannah Research Institute, Ayr KA6 5HL, UK
S. A. McNeillie
Affiliation:
Hannah Research Institute, Ayr KA6 5HL, UK

Summary

The transport of α-aminoisobutyric acid (AIB) by lactating rat mammary tissue has been examined. AIB uptake by mammary tissue was via both Na+-dependent and Na+-independent pathways. AIB uptake via the Na+-dependent pathway was inhibited by (methylamino)isobutyric acid (MeAIB) whereas AIB uptake via the Na+-independent pathway was blocked by 2-aminobicyclo[2, 2, 1]-heptane-2-carboxylic acid (BCH). A small fraction of AIB influx persisted in the presence of both MeAIB and BCH. The Na+-independent moiety of AIB uptake was strongly inhibited by phenylalanine, tryptophan, leucine, isoleucine and methionine. AIB efflux from mammary tissue slices was found to be both Na+-dependent and Na+-independent. Trans-stimulation of AIB efflux by other amino acids was not observed; in contrast, external phenylalanine, tryptophan and leucine inhibited AIB efflux. The results are largely consistent with the presence of systems A and L in lactating rat mammary tissue. However, the Na+-independent fraction of AIB transport may represent transport via a tissue specific form of system L.

Type
Original Articles
Copyright
Copyright © Proprietors of Journal of Dairy Research 1994

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

Allen, J. C. 1988 Sodium and potassium content and viability of mouse mammary gland tissue and acini. Journal of Dairy Science, 71 633642Google Scholar
Barker, G. A. & Ellory, J. C. 1990 The identification of neutral amino acid transport systems. Experimental Physiology 75 326Google Scholar
Baumrucker, C. R. 1985 Symposium: Nutrient uptake across the mammary gland. Amino acid transport systems in bovine mammary tissue. Journal of Dairy Science 68 24362451Google Scholar
Bickerstaffe, R., Annison, E. F. & Linzell, J. L. 1974 The metabolism of glucose, acetate, lipids and amino acids in lactating cows. Journal of Agricultural Science 82 7185Google Scholar
Christensen, H. N. 1975 Recognition sites for material transport and information transfer. Current Topics in Membranes and Transport 6 227258Google Scholar
Christensen, H. N. 1990 Role of amino acid transport and countertransport in nutrition and metabolism. Physiological Reviews 70 4377Google Scholar
Christensen, H. N., Handlogten, M. E., Lam, I., Tager, H. S. & Zand, R. 1969 A bicyclic amino acid to improve discriminations among transport systems. Journal of Biological Chemistry 244 15101520Google Scholar
Christensen, H. N., Oxender, D. L., Liang, M. & Vatz, K. A. 1965 The use of N-methylation to direct the route of mediated transport of amino acids. Journal of Biological Chemistry 240 36093616CrossRefGoogle Scholar
Clark, J. H., Spires, H. R. & Davis, C. L. 1978 Uptake and metabolism of nitrogenous compounds by the lactating mammary gland. Federation Proceedings 37 12331238Google Scholar
Davis, S. R., Bickerstaffe, R. & Hart, D. S. 1978 Amino acid uptake by the mammary gland of the lactating ewe. Australian Journal of Biological Sciences 31 123132CrossRefGoogle Scholar
Enders, R. H., Judd, R. M., Donohue, T. M. & Smith, C. H. 1976 Placental amino acid uptake. III. Transport systems for neutral amino acids. American Journal of Physiology 230 706710Google Scholar
Fleet, I. R. & Mepham, T. B. 1985 Mammary uptake of amino acids and glucose throughout lactation in Friesland sheep. Journal of Dairy Research 52 229237Google Scholar
Kelley, D. S. & Potter, V. R. 1978 Regulation of amino acid transport systems by amino acid depletion and supplementation in monolayer cultures of rat hepatocytes. Journal of Biological Chemistry 253 90099017Google Scholar
Mepham, T. B. 1982 Amino acid utilization by lactating mammary gland. Journal of Dairy Science 65 287298Google Scholar
Mepham, T. B., Overthrow, J. I. & Short, A. H. 1985 Epithelial cell entry and exit competition amongst amino acids in the isolated perfused lactating mammary gland of guinea pig. In Carrier Mediated Transport of Solutes from Blood to Tissue, pp. 369372 (Eds Yudilevich, D. L. and Mann, G. E.). London: LongmanGoogle Scholar
Metcalf, J. A., Sutton, J. D., Cockburn, J. E., Napper, D. J. & Beever, D. E. 1991 The influence of insulin and amino acid supply on amino acid uptake by the lactating bovine mammary gland. Journal of Dairy Research 74 34123420Google Scholar
Neville, M. C., Lobitz, C. J., Ripoll, E. A. & Tinney, C. 1980 The sites for α-aniinoisobutyric acid uptake in normal mammary gland and ascites tumor cells. A comparative study of mouse tissue in vitro. Journal of Biological Chemistry 255 73117316CrossRefGoogle Scholar
Oxender, D. L. 1965 Stereospecificity of amino acid transport for Ehrlich tumor cells. Journal of Biological Chemistry 240 29762982Google Scholar
Oxender, D. L. & Christensen, H. N. 1963 Distinct mediating systems for the transport of neutral amino acids by the Ehrlich cell. Journal of Biological Chemistry 238 36863699Google Scholar
Pocius, P. A. & Baumrucker, C. R. 1980 Amino acid uptake by bovine mammary slices. Journal of Dairy Science 63 746749Google Scholar
Shennan, D. B. 1989 Evidence for furosemide-sensitive Na+–K+–Cl co-transport in lactating rat mammary tissue. Quarterly Journal of Experimental Physiology 74 927938Google Scholar
Shennas, D. B. 1992 Salicylate-induced cation fluxes across biological membranes. A study of the underlying mechanism. Biochemical Pharmacology 44 645650CrossRefGoogle Scholar
Shotwell, M. A., Kilberg, M. S. & Oxender, D. L. 1983 The regulation of neutral amino acid transport in mammalian cells. Biochimica et Biophysica Acta 737 267284Google Scholar
Thier, S. O., Blair, A., Fox, M. & Segal, S. 1967 The effect of extracellular sodium concentrations on the kinetics of α-aminoisobutyric acid transport in the rat kidney cortex slice. Biochimica et Biophysica Acta 135 300305Google Scholar
Yeh, J., Ou, B. & Forsberg, N. E. 1992 Amino acid transport system L in muscle cells: biochemical properties and its relation to protein synthesis. Biochimica et Biophysica Acta 1108 17Google Scholar
Yudilevich, D. L. & Boyd, C. A. R. (Eds) 1987 Amino Acid Transport in Animal Cells. Manchester: University PressGoogle Scholar