title: Volume-activated taurine efflux from the in situ perfused lactating rat mammary gland.
abstract: The effect of cell swelling on the efflux of amino acids from the in situ perfused lactating rat mammary gland has been examined. Cell swelling, induced by a hyposmotic shock, increased the fractional release of [3H]taurine. In contrast, a hyposmotic shock did not stimulate the efflux of D-[3H]aspartate, suggesting that the effect of a hyposmotic challenge on taurine release cannot be attributed to cell lysis. Volume-activated taurine efflux was reversible, dependent upon the extent of the osmotic challenge and inactivated with a prolonged hyposmotic shock. The release of taurine was also reversibly increased following isosmotic cell swelling (using urea). The results confirm the presence of a volume-sensitive taurine efflux transport system in lactating rat mammary tissue and suggest that the volume-activated amino acid efflux pathway is located at the blood-facing aspect of the mammary epithelium.
authors.affiliation: Hannah Research Institute, Ayr, Scotland, UK.
authors.forename: D T
authors.initials: DT
authors.lastname: Calvert
authors.forename: D B
authors.initials: DB
authors.lastname: Shennan
mesh_terms: D000818:Animals; D001692:Biological Transport / Q000502:physiology; D048429:Cell Size; D005260:Female; D007774:Lactation / Q000502:physiology*; D008321:Mammary Glands, Animal / Q000166:cytology / Q000378:metabolism*; D009997:Osmotic Pressure; D010477:Perfusion; D051381:Rats; D017208:Rats, Wistar; D013654:Taurine / Q000378:metabolism*
chemical_list: D013654:Taurine