난소적출후 유발된 흰쥐의 골다공증에서 Estradiol의 효과에 관한 소주골의 형태계측학적 연구 = Morphometric Study on the Effects of Estradiol in the Oophorectomy Induced Osteoporosis in Rat

다국어 초록 (Multilingual Abstract)

Postmenopausal osteoporosis is known to be related to estrogen deficiency and give rise to spine and hip fracture in old person. The purpose of this expreimental study is to investigate whether or not the replacement estrogen administration could improve the process of esblished osteoporosis induced by bilateral oophorectomy in rats.
Sprague-Dawley rats, aged five months, were seperated into two groups, group 1 was the control group that had oophorectomy alone without estradiol treatment. Group 2 was the experimental group, in which estradiol adminitration started at fourth week after oophorectomy. Five rats were killed weekly until the eighth week after oophorectomy. For each group, both tibia, lumbar vertebra & ilium were harvested. Histological analysis and histomorphometric measurements of trabecular bone area of proximal tibia, ilium & lumbar vertebra(L_6) were done by quantitative image analysis system.
Following results were observed :
Histological study revealed mild to moderate loss of trabecular bone area at the 5th week after bilateral oophorectomy followed by more advanced osteoporosis at 7th to 8th week. These osteoporotic changes were delayed and improved by estradiol therapy after 3rd to 4th week of treatment. Similar tendency of these effects were noted also in lumbar vertebra, ilium and upper tibia. Histopathology of the bone revealed that bone loss induced by bilateral oophoretomy occurred mainly in the trabecular bone.
Histomorphometric analysis also revealed that mild to moderate decrease of the trabecular bone areas after bilaterial oophorectomy with estradiol treatment were noted in lumbar vertebra, ilium and tibia.
Based on this short term therapy, estradiol treatment appeared to improve the osteoporosis either by partially restoring the trabecular bone mass or delaying the progression the osteoporotic process in rat.