摘要目的:探讨慢性肾衰竭（chronic renal failure，CRF）幼鼠胫骨生长板软骨细胞初级纤毛高表达加速软骨细胞分化的机制。方法:选取雄性4周龄SD大鼠40只，体重（98±3）g，随机分为对照组（蒸馏水， n=20）和CRF组（腺嘌呤150 mg·kg -1·d -1， n=20），连续灌胃6周后处死幼鼠，采用胫骨制作组织学切片比较生长板长度，免疫荧光检测软骨细胞初级纤毛表达率、Wnt/β-catenin信号通路关键蛋白β联蛋白（β-catenin）表达水平；体外培养两组幼鼠胫骨生长板软骨细胞至第3代，免疫荧光检测软骨细胞初级纤毛表达率及印度刺猬蛋白（Indian hedgehog，IHH）和Wnt/β-catenin通路拮抗蛋白糖原合成酶激酶3β（glycogen synthase kinase 3β，GSK3β）表达水平；应用免疫共沉淀检测IHH与GSK3β之间的作用关系。 结果:与对照组相比，CRF组组织学切片生长板相对长度变短[（0.51±0.11）比（1.00±0.08）， t=16.11， P<0.001]，软骨细胞初级纤毛表达率增高[（26.3±5.5）%比（7.6±1.9）%， t=14.37， P<0.001]，软骨细胞β-catenin蛋白表达增多[（7.1±2.0）分比（3.6±1.0）分， t=7.10， P<0.001]。体外培养结果显示，与对照组相比，CRF组软骨细胞初级纤毛表达率增高[（31.4±8.2）%比（12.5±3.1）%， t=9.64， P<0.001]，IHH蛋白表达增多[（1 360±270）比（310±84）， t=16.61， P<0.001]，而两组GSK3β蛋白表达差异无统计学意义[（850±195）比（780±140）， t=1.30， P=0.200]。免疫共沉淀检测结果显示，CRF组GSK3β蛋白与IHH蛋白在软骨细胞内存在直接相互作用。 结论:CRF幼鼠胫骨生长板软骨细胞初级纤毛表达增多，相关蛋白IHH表达增多，IHH蛋白与Wnt/β-catenin信号通路拮抗蛋白GSK3β存在直接作用，导致Wnt/β-catenin信号通路激活、软骨细胞加速分化，最终导致生长板出现闭合趋势。

abstractsObjective:To explore the mechanism of highly expressed primary cilia in tibial growth plate chondrocytes accelerating chondrocytes differentiation in young rats with chronic renal failure (CRF).Methods:Forty male 4-week-old SD rats weighing (98±3) g were randomly divided into control group (intragastric administration with distilled water, n=20) and CRF group (intragastric administration with adenine suspension 150 mg·kg -1·d -1, n=20). All the young rats were sacrificed after continuous gavage for 6 weeks. The length of the growth plate was measured with histological sections. Immunofluorescence (IF) was used to detect the expression rate of primary cilia and the level of β-catenin, the key protein of Wnt/β-catenin signaling pathway in tibial growth plate chondrocytes. Chondrocytes isolated from growth plate in two groups were cultured in vitro to P3 generation, and the expression rate of primary cilia in chondrocytes, the levels of Indian hedgehog (IHH) and glycogen synthase kinase 3β (GSK3β) were detected by IF. Co-immunoprecipitation was used to detect the relationship between IHH and GSK3β. Results:Compared with the control group, the relative length of the growth plate was shorter in histological sections [(0.51±0.11) vs (1.00±0.08), t=16.11, P<0.001], the expression rate of primary cilia was higher [(26.3±5.5)% vs (7.6±1.9)%, t=14.37, P<0.001], and the level of β-catenin increased [(7.1±2.0) scores vs (3.6±1.0) scores, t=7.10, P<0.001] in CRF group. In vitro, the expression rate of primary cilia was higher in CRF group chondrocytes [(31.4±8.2)% vs (12.5±3.1)%, t=9.64, P<0.001] than that in control group. The level of IHH in CRF group increased than that in control group [(1 360±270) vs (310±84), t=16.61, P<0.001]. There was no significant difference in GSK3β level of chondrocytes between the two groups [(850±195) vs (780±140), t=1.30, P=0.200]. There was a direct interaction between IHH and GSK3β in CRF group chondrocytes. Conclusions:The expression levels of primary cilia and related protein IHH increase in tibial growth plate chondrocytes of CRF young rats. The IHH protein plays a direct interaction with GSK3β protein, Wnt/β-catenin signaling pathway antagonist, which leads to the activation of Wnt/β-catenin signaling pathway and final accelerated differentiation of chondrocytes. The rapid differentiation of chondrocytes causes the closing trend of growth plate.