AJP - Endocrinology and Metabolism, Vol 246, Issue 3 216-E220, Copyright © 1984 by American Physiological Society
A maternal defect is responsible for growth failure in vitamin D-deficient rat pups
R. Brommage and H. F. DeLuca
Vitamin D deficiency was induced in lactating rats and their pups by
placing female rats on a vitamin D-deficient diet immediately after mating.
Evidence of vitamin D deficiency included undetectable plasma levels of
25-hydroxyvitamin D3 in the dams, maternal hypocalcemia, the lack of pup
growth, and pup hypocalcemia following starvation. This method of producing
vitamin D-deficient pups was then used to determine whether the failure of
vitamin D-deficient pups to grow properly results from a maternal or
neonatal defect. Vitamin D-deficient dams and pups were injected with
either vitamin D3 or the ethanol vehicle, and pup growth was monitored over
the subsequent 6 days. Providing vitamin D3 to the pups directly had no
effect on their growth, but administering vitamin D3 to the dams resulted
in a tripling of the pup growth rate. The failure of vitamin D3 to promote
pup growth when given directly to the pups was not the result of their
inability to metabolize the vitamin because these pups converted
[3H]-vitamin D3 to 25(OH)D3, 24,25(OH)2D3, and 1,25(OH)2D3 as determined by
comigration with standards on both straight and reverse phase
high-performance liquid chromatography systems. These results demonstrate
that a maternal defect is responsible for the growth failure observed in
vitamin D-deficient rat pups.
