Compartmental Model of Perfusion Studies of Intestinal Uptake of B-6 Vitamers in Rats
Experimental Biology Conference
We have been working toward developing a compartmental model of vitamin B-6 metabolism which can respond appropriately to a variety of circumstances. In this project we used data from three intestinal perfusion reports (Mehansho et al., J.Nutr., 109:1542, 1979; Hamm et al., J.Nutr. 109:1552, 1979; Buss et al., J.Nutr. 110:1655, 1980) and SAAM II (Univ. of Washington, Seattle, WA) to develop a 25 compartment model describing the movement of vitamers from the lumen to the mucosa and into the perfusate. The model includes binding kinetics in the mucosa to generate steady state conditions over extended time. Although it is frequently assumed that pyridoxic acid(PA) is produced from pyridoxal, PA concentrations were mostly closely correlated with pyridoxal phosphate (PLP). Therefore, the model includes fluxes between PLP and PA. The model also includes erythrocyte compartments to account for increased uptake when erythrocytes were present in the perfusate or in whole animal experiments. The final model describes the intestinal uptake of pyridoxine, pyridoxal, pyridoxal phosphate, pyridoxamine and pyridoxamine phosphate over a wide range of concentrations and in response to phosphate inhibition.
B-6 Vitamers, compartmental modeling
Biochemistry, Biophysics, and Structural Biology
Stephen P. Coburn and Douglas W. Townsend (2011).
Compartmental Model of Perfusion Studies of Intestinal Uptake of B-6 Vitamers in Rats. Presented at Experimental Biology Conference, Washington, DC.