Vitamin D and the supravalvar aortic stenosis syndrome. The transplacental effects of vitamin D on the aorta of the rabbit.

RECENT REPORTS have indicated that idiopathic infantile hypercalcemia, a disease related to deranged vitamin D metabolism, -4 may be a feature of the nonfamilial, congenital supravalvar aortic stenosis syndrome.5 8 Other manifestations of this syndrome include mental retardation, a peculiar "elfin" facies, narrowing of peripheral pulmonary and systemic arteries, strabismus, inguinal herniae, and dental abnormalities.9 Congenital supravalvar aortic stenosis and peripheral pulmonary arterial stenosis also occur in a familial and a sporadic form unassociated with the other features of the syndrome.10-13 It is not known if the multiplesystem involvement in the supravalvar aortic stenosis syndrome is genetically determined or whether some or all of the features are related to a derangement of maternal or fetal vitamin D metabolism, or a combination of the two. A paucity of information exists regarding the effects on the fetus of induced maternal hypervitaminosis D, and there appears to be no direct evidence for transplacental passage of vitamin D.'4-16 Studies concerning hypervitaminosis D in the nonpregnant animal emphasize the vascular toxicity of the vitamin.17-23 Administration of excessive vitamin D to animals has been shown to produce doserelated vascular lesions, ranging from suben-