Effects Of Vitamin A Defficiency And Supplement On Skeletal Development Of Rats

EFFECTS OF VITAMIN A DEFICIENCY AND SUPPLEMENT ON SKELETAL DEVELOPMENT OF RATSObjective: To study the effects of vitamin A deficiency (VAD) and supplement on skeletal development of rats.Methods: 18 female Wistar rats were randomly divided into VAD, supplement and control groups. The rats were fed with vitamin A (VA) 400IU/kg and 6500IU/kg diets, respectively, starting from 3 weeks before pregnant onwards, until young rats aged 7 weeks old. The supplement groups were randomly divided into three groups, and they were changed to feed with vitamin A 6500Iu/kg diets respectively from 14 days after pregnant, 0 day or 4 weeks after birth to 7 weeks age old. When they were 0 day, 4 weeks and 7 weeks old, every group young rats' body weight, the length of tibia, the height, width of the rat proximal tibial growth plate, VA levels in serum were detected, and the histology of growth plate was also observed, the expression of RARγ was measured in cartilage of growth plate at 7 weeks old.Results: (1) The VA levels in serum were lower than the control. (2) The body weights and tibial length were decreased compared with the control. (3) The heights of growth plate were significantly lower than those of the control. (4) The histology of growth plate was very different, and the height of the rat proximal tibial growth plate was reduced by inhibiting proliferative and hypertrophic zone. (5)The expression of RARγ in VAD rats was lower than those of the control and supplement.Conclusions:(1) VAD can affect skeletal development of young rats by inhibiting growth plate. (2) The earlier to supplement vitamin A, the more effective to change the effect of inhibiting.