Relationship of Dietary Protein and Food Intake to Pyridoxine Nutrition in the Rat

Publisher Website
Google Scholar
Abstract
The effects of various dietary regimens (commonly encountered among human populations) on pridoxine nutrition have been studied, using the rat. The regimens studied were I, a normal diet, II, a normal diet without pyridoxine, III, restricted intake of normal diet without pyridoxine, IV, high protein diet without pyridoxine, and V, non-protein diet without pyridoxine, all for a 4-week period. Regimen IV, above, was found to produce the same degree of loss of vitamin B6 activity (approximately 75%) from representative organs of the rat as a 20% level of the same protein (II), after 4 weeks. In this case also, the change in weight was found to correlate poorly with tissue pyridoxine levels. When regimen III was employed, vitamin B6 in the organs was decreased to the same extent as with diet II. Diet V caused only a 50 to 25% loss of vitamin B6 in the organs, depending on the one studied. When rats receiving diets II to V for 4 weeks were fed a pyridoxine-deficient, 20% protein ration, no further changes in the vitamin B6 concentrations of the organs were observed in groups II to IV in two weeks. However, in group V these concentrations were decreased further to the same levels as for the other groups. A return of groups II to V to a complete, 20% protein ration brought all concentrations of vitamin B6 in the organs to normal within two weeks. During this period, the relative weight gain among the various groups decreased in the following order: III, II, V, and IV. The implications of our findings on the relationships of extra-vitamin dietary factors to pyridoxine nutrition have been discussed.