Experimental Study of Osteoporosis

【研究目的】通过实验评估吸收不良、卵巢切除、低钙饮食和糖尿病等危险因素对骨质疏松的影响。【材料与方法】对10只成年小猎犬进行胰十二指肠切除术，诱导其吸收不良。其中一半采用Child法重建，其余采用改良法重建。5只存活6个月，其中2只采用Child手术，其余采用改良手术，经2次静脉注射四环素后死亡。对第三腰椎未钙化切面进行组织形态学评价。7 ~ 8月龄wistar退休大鼠的持续危险因素包括卵巢切除术、低钙饮食、链脲佐菌素注射诱导的糖尿病。它们要么单独装载，要么与一个或两个组合装载。低钙饮食每100克含钙6.0毫克。腹腔注射链脲佐菌素，剂量为30mg/kg，血糖超过300mg/dl时可检出糖尿病。假手术大鼠作为对照。四环素标记后实验3或6个月处死。用Villanueva法染色的胫骨近端未钙化地面切片，用Cosmozone 1S （Nikon）进行组织形态学评价。【结果与讨论】所有犬体重均下降0.3 ~ 5kg，且均持续脂肪吸收不良，对葡萄糖的耐受性下降。除Child手术外，胰十二指肠切除术犬骨体积平均值未见明显下降。与对照组相比，与骨形成有关的参数，包括类骨表面的程度和四环素标记被抑制。这种受损的骨形成最终会导致骨质流失。实验3个月时，所有大鼠均在单因素和一种或两种因素的联合作用下骨体积明显减少。6个月时骨体积的减少更为明显，特别是在糖尿病持续的大鼠中。综合危险因素对骨质流失的影响比单一因素的影响更明显。实验3个月时，糖尿病大鼠的骨形成率明显下降，主要是由于基质形成受损。少

[Purpose of the study] The effect of risk factors of developing osteoporosis including malabsorption, ovariectomy, low calcium diet, and diabetes was experimentally evaluated.[Materials and Methods] Malabsorption was induced by pancreatoduodenectomy in 10 adult beagles. Half of them were reconstructed by Child's procedure, and the remaining by modified one. Five dogs survived for 6 months, two of them operated by Child's procedure, and the others by modified method, were killed after giving tetracycline twice intravenously. Undecalcified cut sections of 3rd lumbar spine were evaluated histomorphometrically.Wistar-retired rats aging 7 to 8 months were sustained risk factors consisting of ovariectomy, low calcium diet, diabetes induced by streptozotocin injection. They were loaded either alone or in combination with one or two. Low calcium diet contains 6.0mg calcium/100g. Streptozotocin was given intraperitoneally at dose of 30mg/kg, and diabetes was detected by hyperglycemia more than … More 300mg/dl. Sham-operated rats were served as controls. They were sacrificed at 3 or 6 months of experiment after tetracycline labeling. Undecalcified ground sections of the proximal tibia, stained with Villanueva method, were histomorphometrically evaluated with Cosmozone 1S (Nikon).[Results and discussion] All dogs lost their weight by 0.3 to 5kg, and they all sustained malabsorption of fat and lost their tolerance to glucose. Mean value of bone volume did not show significant decrease in pancreatodudenectomized dogs, except for one operated by Child's procedure. Parameters relating to bone formation including an extent of osteoid surface and tetracycline labeling were depressed compared with controls. This impaired bone formation would eventually bring about bone loss.All rats sustained both single factor and in combination with one or two lost their bone volume significantly at 3 months of experiment. Decrease of bone volume at 6 months was more apparent, particularly in diabetes-sustaind rats. The effect of combination of risk factors on bone loss was more dominant compared with that of single factor. Bone formation rate at 3 months of experiment was depressed in diabetes rats in particular, mostly because of impaired matrix formation. Less