Some Effects of Cations and of Water Absorption on Intestinal Hexose,Glycine and Cation Absorption. ∗

Abstract

Summary

Fourteen mMolar hexose or glycine plus 100 to 210 mMolar sodium or non-sodium salts were perfused through jejunal or Heal loops in non-anesthetized dogs. Net water movements changed in response to the chemical identity as well as to the osmolarity of the perfusate. In general, hexose and glycine absorption rates decreased as water absorption rates decreased. At given water absorption rates however, glucose and galactose absorption rates were lower when K or NH4 salts were substituted for Na salts. Fructose, sorbose and glycine absorption rates did not differ between sodium and non-sodium per-fusates. In a second series, .310 osmolar solutions containing varying proportions of NaCl and KC1, NaCl and NH₄C1, or KC1 and NH₄C1 were perfused. Cation absorption rates increased directly with the concentration of the same ion and with water absorption rates. In addition, NH₄ and Na absorption rates decreased as (K) increased, Na and K absorption decreased as (NH₄) increased, and NH₄ absorption decreased as (Na) increased.

I thank Esther Rasson and Cheryl Maxwell for technical help.