Abstract
Abstract 1. 1. Active transport of amino acids in rat kidney cortex slices diminished as the Na+ concentration of the medium was decreased below physiologic levels. In Na+-free media, active transport of glycine and α-amino [ i -14C]isobutyric acid was abolished, but active transport of lysine persisted. 2. 2. Lysine transport was found to be mediated by two mechanisms—one Na+ dependent and ouabain sensitive, and the other independent of Na+ and insensitive to ouabain. 3. 3. Maximal transport of amino acids occurred over a narrow range of medium K+ concentrations, falling off at higher and lower K+ levels. 4. 4. Substitution of other ions for Na+ in the medium caused significant alterations of the intracellular and extracellular fluid spaces of the tissues. 5. 5. Replacement of medium Na+ by K+ resulted in tissue swelling and suppression of amino acid transport beyond that caused by the absence of Na+. 6. 6. The common ionic requirements of kidney ATPase systems and of the mechanisms for active transport of certain amino acids suggest that these processes may be intimately related.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
