Nickel deficiency alters nickel flux in rat everted intestinal sacs

This study was conducted to determine nickel absorption in nickel-deficient rats. Jejunal segments obtained from dietary nickeldepleted (13 μg nickel/kg diet) and nickel-control (1 mg nickel/kg diet) adult rats from the first generation, and suckling pups from the second offspring were used. The nickel transfer across the intestinal epithelium and nickel uptake into the intestine were measured by use of everted jejunal sacs using a wide range of nickel concentrations administered on the luminal side (1.1 x 10^-8 M til 1.0 x 10^-4 M). Both the intestinal nickel transfer and nickel uptake were influenced by the dietary nickel supply in rat offspring, but not in the adult rats from the first generation. However, in nickel-deficient offspring, the nickel transfer across the small intestine was higher than in nickelcontrol offspring. This difference was greater using low intraluminal nickel concentrations than high nickel concentrations, and was significant at 1.1 x 10^-8 M, 6.1 x 10^-8 M, 5.1 x 10^-7 M, 1.0 x 10^-6 M, and 5.0 x 10^-6 M. Also, nickel uptake into the intestine was somewhat greater in nickel-deficient rat pups than in nickel-control pups, and significant using 1.1 x 10^-7 M and 1.0 x 10^-6 M nickel. A definite saturation type kinetic for the intestinal nickel absorption in relation to the intraluminal nickel concentration could not be observed.