双侧卵巢切除山羊不同时间段骨形态计量学与骨密度的变化

Bone histomorphometry and bone mineral density changes in ovariectomized goats at regular intervals

采用骨病理形态学、骨计量学与骨密度测定法 ,动态观察了山羊假手术组 (Sham)和双侧卵巢切除组 (OVX)术前、术后 3月、6月、12月和 18月各不同时间段髂骨骨病理形态学、骨小梁体积百分比 (Vv% ) ,骨小梁宽度和腰椎 (L2 - L4 )骨密度的变化。结果显示 :Sham组术后各时间段髂骨骨病理形态学、骨小梁体积百分比和骨小梁宽度无明显变化 (P>0 .0 5)。L2 ～ L4 骨密度呈缓慢上升趋势 ,至术后 18月比术前增高 38% ,差异有显著性 (P<0 .0 5)。而 OVX组术后 3月髂骨骨结构形态出现变化 ,骨小梁数量轻度减少 ,相互连接分开 ;术后 6月骨小梁数量进一步减少 ,骨小梁宽度减小 ,骨髓腔扩大 ,骨小梁游离成小块状 ;至术后 12月骨小梁宽度有所增大 ,但仍低于术前。骨计量学显示 ,骨小梁体积百分比在术后 3月明显下降 ,术后 6月进一步下降 ,持续到术后 12月 ;与术前相比差异有显著性 (P<0 .0 1)。其平均骨小梁宽度在术后 3月也开始降低 (P<0 .0 1) ,术后 6月达最低值 (P<0 .0 1) ,术后 12月逐步恢复 ,趋于正常。术后 3月和 6月 ,Sham组骨小梁体积百分比和平均骨小梁宽度明显高于 OVX组 ,有显著性差异 (P<0 .0 5)。 OVX组中 L2 ～ L4 骨密度的变化趋势与 Sham组相似 ,术后 18月明显高于术前 (P<0 .0 5) 。

Objective\ To investigate dynamically the bone histomorphometric change of ilium and the changes of bone mineral density (BMD) of lumbar spines in ovariectomized goats at regular intervals.Methods\ Twenty she goats,two years old,were randomly divided into two groups,the sham operated group and the ovariectomized group.Iliac crest biopsies were made and bone mineral density was measured in these two groups before and 3, 6, 12 and 18 months after ovariectomy. Results The bone structure in trabecular bone remained relatively constant in the sham operated group at regular intervals.The level of BMD of L 2-4 at 18 months after operation was higher than that before operation in the sham operated group.The trabecular quantity decreased and the trabeculae were disconnected in OVX group at 3 months after ovariectomy,and the TBV/TTV (trabecular bone volume/total tissue volume) and MTW(mean trabecular width) at 3 months after ovariectomy were lower than those before ovarie ctomy.The low level trabecular quantity continued in the whole time course.The BMD obviously decreased at 6 months after ovariectomy in OVX group.The level of BMD of L 2-4 at 18 months were higher than that before operation in the OVX group. Conclusion The bone mass and BMD of trabecular bone decrease obviously in ovariectomized goats,which is related to estrogen deficiency after ovariectomy.The increasing level of BMD of L 2-4 in both sham operated group and OVX group may be related to increase in body weight of the goats.