Effect of $1{\alpha},\;25\;Dihydroxyvitamin\;D_3$ on Osteoporosis in Rats

$1{\alpha},\;25\;Dihydroxyvitamin\;D_3$이 랫드 골다공증에 미치는 영향

Vitamin D is one of important factors involved in the regulation of bone metabolism. In osteoporosis, the therapeutic effect of vitamin D on the healing process has still been controversial. To confirm the effects of $1{\alpha},\;25\;Dihydroxyvitamin\;D_3$ on the osteoporosis, the change of bone mineral density and the histologic changes of osteoporotic femur were examined comparatively in normal control group (positive control), CFA control group (negative control), CFA+$1{\alpha}$, 25 dihydroxyvitamin $D_{3}\;0.01{\mu}g/kg$ group (Vit $D_{3}L$) and CFA+$1{\alpha}$, 25 dihydroxyvitamin $D_{3}\;0.1{\mu}g/kg$ group (Vit $D_{3}H$) after osteoporosis was induced by single injection of complete Freund's adjuvant (CFA) in rats. The value of bone mineral density and bone mineral content of femur was increased in both Vit $D_{3}L$ and Vit $D_{3}H$ than CFA control, and the increase rate of that was higher in Vit $D_{3}H$ than Vit $D_{3}L$. In CFA control, the size of the bone marrow cavities significantly increased and the width from the bone marrow cavity and cortex significantly decreased than normal control. In Vit $D_{3}H$ and Vit $D_{3}L$, the increase rate of the size of bone marrow cavity and the decrease rate of the width from the bone marrow cavity and cortex was depressed than CFA control. These results suggest that $1{\alpha},\;25\;Dihydroxyvitamin\;D_3$ has therapeutic effect on adjuvant-induced osteoporosis in rats.

Sprague-Dawley rat에 complete Freund's adjuvant (CFA)를 투여하여 유발한 골다공증에 미치는 $1{\alpha}$, 25 dihydroxyvitamin $D_3\;(Vit\;D_3)$의 효과를 알아보기 위하여 실험동물을 정상 대조군, CFA 투여 대조군, CFA 투여후 $1{\alpha}$, 25 dihydroxyvitamin $D_3\;0.01{\mu}g/kg$ 투여군 (Vit $D_{3}L$) 및 $0.1{\mu}g/kg$ 투여군(Vit $D_{3}H$)으로 분류하여 경구로 3주간 투여하였다. 골다공증의 억제 효과를 알아보기 위하여 골밀도와 골함유량의 변화 및 주사전자현미경적 소견을 관찰한 결과 다음과 같은 결론을 얻었다. 골밀도와 골함유량은 $1{\alpha}$, 25 dihydroxyvitamin $D_3$ 투여용량과 부위에 따라 차이가 있었는데 Vit $D_3$ 투여군이 CFA 투여 대조군과 비교하여 골밀도와 골함유량이 증가하였으며 Vit $D_{3}H$군이 Vit $D_{3}L$군보다 좀 더 효과적이었다. 대퇴골의 주사전자현미경적 소견은 Vit $D_3$ 투여군의 골피질과 골소주의 손상이 CFA 투여 대조군보다 억제되었음을 볼 수 있었으며 Vit $D_{3}H$ 투여군이 Vit $D_{3}L$ 투여군보다 좀 더 효과적이었다. 이상의 결과를 종합해 보면 $1{\alpha}$, 25 dihydroxyvitamin $D_3$의 투여는 CFA에 의해 유발된 rat의 골다공증 모델에서 골다공증의 진행을 억제하였고 Vit $D_{3}H$ 투여군이 Vit $D_{3}L$ 투여군보다 좀 더 효과적이었다.