Skip to main content
ARS Home » Plains Area » Grand Forks, North Dakota » Grand Forks Human Nutrition Research Center » Dietary Prevention of Obesity-related Disease Research » Research » Publications at this Location » Publication #65768
Title: DIETARY HISTIDINE (HIS) LOADING HAS LITTLE EFFECT ON THE INTERACTION OF NICKEL (NI) AND FOLIC ACID (FA) IN RATS

Author
item Poellot, Rhonda Lee
item Uthus, Eric

Submitted to: Journal of Federation of American Societies for Experimental Biology
Publication Type: Abstract Only
Publication Acceptance Date: 4/14/1996
Publication Date: N/A
Citation: N/A

Interpretive Summary:

Technical Abstract: Previous studies have shown that dietary nickel (Ni) and folic acid (FA) interact in the rat. Following dietary histidine (His) injection the urinary excretion of formiminoglutamic acid (FIGLU) by FA-deficient rats increased and Ni deprivation exacerbated this increase. This finding led to the hypothesis that Ni was affecting the catabolism of His, possibly at the FA-dependent, formiminotransferase step. Thus, a study was performed to determine the effects of high dietary His on Ni deprivation in rats fed either FA-deficient or FA-adequate, diets. The experiment was a 2x2x2 design with dietary variables of Ni (0 or 1 ug/g), FA (0 or 4 mg/kg), and His (0 or 15 g/kg). All groups (N=6/group) received 10 g succinyl- sulfathiazole/kg diet. After about 8 wk the rats (no bolus IP dose of His) were placed in metabolic cages and urine was collected for 20 hr. Ten days after collection of urine, the experiment was terminated. Urine FIGLU was increased by either FA deprivation or by His feeding. His feeding significantly increased FIGLU in FA-deprived rats but not in FA- adequate animals. Ni did not affect FIGLU. Ni supplementation increased plasma B12 in FA-deprived rats but not in FA-adequate rats. Ni, His, and FA tended (P=0.058) to interact to affect plasma FA. In FA-adequate rats, Ni supplementation had no effect on plasma FA in non-His-supplemented rats; in the His-fed rats, Ni supplementation tended to decrease plasma FA. These effects were not seen in the FA-deprived rats. These results indicate that Ni has a biological role associated with the vit B12 and FA- dependent pathway of methionine metabolism or possibly directly with FA metabolism itself.