甲状旁腺素(1-34)对去卵巢大鼠掺锶羟基磷灰石涂层种植体骨整合的影响

The effect of parathyroid hormone(1-34) on implant osseointegration of strontium-containing hydroxyapatite coating in ovariectomized rats

目的探索甲状旁腺素(1-34)对去卵巢大鼠掺锶羟基磷灰石涂层种植体骨整合的影响。方法行双侧卵巢摘除术后12 w,大鼠随机分为Control组、PTH组、Sr组及PTH+Sr组,之后分别在双侧股骨植入羟基磷灰石或掺锶羟基磷灰石涂层的钛钉,PTH组及PTH+Sr组术后给予PTH治疗。12 w后处死大鼠取双侧行Micro-CT、组织学及生物力学检测。结果Micro-CT三维重建显示,PTH+Sr组钛棒周围有最多的骨组织形成,微观参数定量结果表明与Control组相比,PTH+Sr组骨体积分数BV/TV增加了2.45倍,骨小梁数量(Tb.N)增加了2.94倍,骨小梁连接密度(Conn.D)增加了2.31倍,骨小梁厚度(Tb.Th)增加了1.56倍,而骨小梁分离度(Tb.Sp)降低了1.65倍(P<0.05)。骨生物力学结果表明,相对Control组而言,Sr组,PTH组及PTH+Sr组的最大推力分别增加了1.27倍、1.36倍及1.61倍(P<0.05)。组织学结果显示12w时,Sr组,PTH组及PTH+Sr组的骨面积比率(BAR)相较于Control组分别提高了1.52倍、1.73倍及2.30倍(P<0.05),其骨-种植体接触率(BIC)分别提高了1.35倍、1.56倍及2.21倍(P<0.05)。结论掺锶羟基磷灰石涂层结合PTH(1-34)可以加强植入体在骨质疏松骨中的骨整合。

Objective To investigate the effect of parathyroid hormone（1-34） on implant osseointegration of strontiumcontaining hydroxyapatite coating in ovariectomized rats. Methods Twelve weeks after bilateral ovariectomy,the rats were randomly divided into control group,PTH group,Sr group,and PTH ＋ Sr group. The HA-coated implants or Sr-HA implants were bilaterally inserted in all OVX rats. Subsequently,rats of PTH and PTH ＋ Sr groups were given the treatment of PTH. In 12 weeks after therapy,all OVX rats were sacrificed and their femurs with implants were harvested and evaluated by micro-CT,histology,and biomechanical tests. Results Three dimensional reconstruction of Micro-CT showed that rats in PTH ＋ Sr group had the largest bone tissue formation around implants. Compared to control group,the bone volume ratio of PTH ＋ Sr group increased by2. 45 times,the trabecular number（Tb. N） increased by 2. 94 times,the connectivity density（Conn. D） increased by 2. 31 times,the trabecular thickness（Tb. Th） increased by 1. 56 times,but the trabecular separation（Tb. Sp） decreased by 1. 65 times（P 〈0. 05）. Bone biomechanical results indicate that,compared with that in the control group,Sr group,PTH group and PTH ＋ Sr group,the maximum push-out force were increased by 1. 27 times,1. 36 times,and 1. 61 times（P 〈 0. 05）,respectively.Histological evaluation revealed that the bone area ratio（BAR） of Sr group,PTH group,and PTH ＋ Sr group increased by 1. 52 times,1. 73 times,and 2. 30 times（P 〈 0. 05）,respectively. Bone implant contact ratio（BIC） increased by 1. 35 times,1. 56 times,and 2. 21 times（P 〈 0. 05）,respectively,when compared with the control group. Conclusion Strontium-containing hydroxyapatite coating combined with PTH（1-34） enhances implant osseointegration in osteoporotic bone.