The rumen and potassium homeostasis: a model
The ruminant has to be able to regulate potassium metabolism over an extremely wide range of intake. When related to body weight, dietary potassium intake of ruminants frequently exceeds that of humans by a factor of over ten, and experimental situations suggest that the toxic threshold for ingestion of potassium is considerably higher. While a number of studies have addressed the outstanding ability of the ruminant kidney to extrude potassium, the role of the rumen in maintaining potassium homeostasis in sheep and cows by serving as a reservoir for the redistribution of potassium has received considerably less attention. Based on current and past studies at the level of the cell, the tissue and the animal, we present a model for the regulation of ruminal transport that may help in the understanding of the variable responses of the rumen epithelium to dietary potassium intake, and the role of magnesium in mediating these responses.
rumen potassium magnesium cation channel patch-clamp sheep
F.Stumpff H.Martens
Department of Veterinary Physiology, Free University of Berlin Oertzenweg 19b, D-14163 Berlin, Germany
国际会议
The 7tb International Symposium on the Nutrition of Herbivores(ISNH-7)(第七届国际草食动物营养研讨会)
北京
英文
936-941
2007-09-16（万方平台首次上网日期，不代表论文的发表时间）