Kaur, SBabbar, H SMahmood, A2009-05-282009-05-281993-06-01Kaur S, Babbar HS, Mahmood A. Effect of pH and sodium ions on intestinal uptake of lysine in rats. Indian Journal of Experimental Biology. 1993 Jun; 31(6): 529-32http://imsear.searo.who.int/handle/123456789/61584Intestinal uptake of lysine in rats progressively decreased with an increase in pH from 5.2 to 8.5, both in the presence and absence of Na+ ions. At pH 5.2 lysine uptake was 30-35% more than that at neutral pH. Na+ activated lysine uptake by 40-50% at pH 5.2 and it was increased to 110-120% at neutral pH. The observed increase in lysine uptake in response to Na+ and H+ gradients was due to enhanced maximal velocity (Vmax), with little change in affinity constant (Kt). Arrhenius analysis revealed a biphasic curve for lysine uptake with transition temperature (Tc) around 20 degrees C (24 degrees C at pH 5.2 in presence of Na+). The energy of activation (Ea) below (16.1-23.4 Kcal/mole) and above (6.7-8.6 Kcal/mole) the Tc was similar at pH 5.2 and 7.0 both in the presence and absence of Na+ ions. The sensitivity of lysine uptake to various inhibitors was also dependent upon pH and Na+ ions.engAnimalsArsenites --pharmacologyDinitrophenols --pharmacologyEthylmaleimide --pharmacologyHarmaline --pharmacologyHydrogen-Ion ConcentrationIntestinal Absorption --drug effectsIodoacetates --pharmacologyIodoacetic AcidIsatin --pharmacologyLysine --pharmacokineticsMaleRatsRats, WistarSodium --pharmacologySodium Compounds --pharmacologySodium-Hydrogen Antiporter --metabolismJournal Article