The effect of changes in osmolality on amino acid transport in the proximal convoluted tubule of the rat kidney.
In order to differentiate between the effect of increased amino acid (substrate) concentration and the accompanying rise in fluid osmolality on renal tubular amino acid transport properties, the transport of cycloleucine has been examined under conditions where the osmolality only was altered with raffinose. In stationary microperfusion experiments it has been demonstrated that an increase in osmolality to 400 mosmol/kg on both sides of the epithelium at once does not alter the active transporting capacity achieved. Although no experimental evidence is yet available, theoretical considerations suggest that neither component of this active transporting capacity, viz. active transepithelial transport rate or the permeability coefficient, would have changed.
D000596:Amino Acids / Q000502:physiology*; D000818:Animals; D003515:Cycloleucine / Q000378:metabolism; D007687:Kidney Tubules, Proximal / Q000502:physiology*; D008297:Male; D009994:Osmolar Concentration; D051381:Rats
D000596:Amino Acids; D003515:Cycloleucine