Effects of vitamin D supplementation on calcium balance and bone growth in young rats fed normal or low calcium diet.
OBJECTIVE
We examined the effect of vitamin D supplementation on bone growth in young rats fed a normal or low calcium diet.


METHODS
Fifty female Sprague-Dawley rats, 6 weeks of age, were randomized by stratified weight method into five groups with 10 rats in each group: baseline control, 0.5% (normal) or 0.1% (low) calcium diet, and 0.5 or 0.1% calcium diet + vitamin D (25 microg/100 g, food intake). Duration of the experiment was 10 weeks.


RESULTS
Vitamin D supplementation stimulated intestinal calcium absorption and increased urinary calcium excretion in rats fed a low or normal calcium diet. Vitamin D supplementation prevented the reduction in periosteal bone gain but enhanced enlargement of the marrow cavity and reduced the maturation-related cancellous bone gain in rats fed a low calcium diet, and increased the maturation-related cancellous and cortical bone gains in rats fed a normal calcium diet.


CONCLUSIONS
This study shows the differential effects of vitamin D supplementation on born growth in young rats fed a normal or low calcium diet.
Iwamoto
J
J
Department of Sports Medicine, Keio University School of Medicine, Tokyo, Japan. jiwamoto@sc.itc.keio.ac.jp
Yeh
J K
JK
Takeda
T
T
Sato
Y
Y
D000818:Animals; D001846:Bone Development / Q000187:drug effects*; D002118:Calcium / Q000008:administration & dosage* / Q000097:blood / Q000378:metabolism*; D004032:Diet; D004305:Dose-Response Relationship, Drug; D005260:Female; D006728:Hormones / Q000097:blood; D007408:Intestinal Absorption; D010758:Phosphorus / Q000097:blood; D051381:Rats; D017207:Rats, Sprague-Dawley; D013977:Tibia / Q000473:pathology; D014807:Vitamin D / Q000494:pharmacology*; D015430:Weight Gain
D006728:Hormones; D014807:Vitamin D; D010758:Phosphorus; D002118:Calcium