Objective: To observe the effect of primary cilia on growth plate chondrocyte proliferation of young rats with chronic renal insufficiency (CRI). Methods: Male 2-week-old Sprague-Dawley rats were randomly divided into two groups (with 10 in each group): Sham group (only left ureter was exposed) and CRI group (left ureter was ligated). Rats were sacrificed 2 weeks after operation and the total length of tibia was measured. Histological sections of tibia were taken to observe the chondrocytes of growth plate proliferative region and the expression rate of primary cilia. Chondrocytes from growth plate in two groups were isolated and cultured in vitro to P3 generation and the chondrocyte proliferation rate at 24 h were detected. The primary cilia expression rate and cilia length of chondrocytes were measured. Western blot was used to detect the expression of intraflagellar transport 88 (IFT88) protein and the gray scale was analyzed. Results: The total length of tibia was shorter in CRI group [(35.84±4.56) mm vs (42.33±3.44) mm, P=0.002]. The results of tibial histological section showed that chondrocytes of growth plate proliferative region were unorganized and the number of chondrocyte with columnar structure was less in CRI group (2.71±1.10 vs 7.68±1.32, P<0.001). The primary cilia expression rate of chondrocytes was higher in CRI group [(35.53±7.41)% vs (18.31±5.12)%, P<0.001]. The chondrocyte proliferation rate at 24 h was lower in CRI group [(11.38±6.10)% vs (24.35±8.46)%, P=0.001]. The primary cilia expression rate of chondrocytes was higher in CRI group [(60.12±7.86)% vs (32.17±8.97)%, P<0.001], and the primary cilia length of chondrocytes was longer in CRI group [(3.54±1.61) μm vs (1.96±0.82) μm, P=0.012]. The protein IFT88 was more highly expressed in CRI group (0.47±0.23 vs 0.17±0.10, P=0.001). Conclusion: The primary cilia expression rate of growth plate chondrocytes was higher in the rats with CRI, resulting in decreased chondrocyte proliferation rate and growth retardation of tibial growth plate.
目的： 观测慢性肾功能不全幼鼠胫骨生长板软骨细胞初级纤毛表达对细胞增殖的影响。 方法： 雄性2周龄SD幼鼠20只，随机分为假手术组（切开暴露左侧输尿管）和慢性肾功能不全（CRI）组（左侧输尿管结扎），每组10只。术后2周处死幼鼠，测量胫骨全长并行组织学切片观测生长板增殖区细胞生长状态及细胞初级纤毛表达率。分别提取两组胫骨生长板区软骨细胞进行体外培养至P3代，检测细胞24 h增殖率，细胞初级纤毛表达率和纤毛长度；Western印迹检测细胞纤毛转运体88（IFT88）蛋白表达水平并进行灰度分析。 结果： CRI组幼鼠胫骨长度短于假手术组[（35.84±4.56）mm比（42.33±3.44）mm，P=0.002]；胫骨生长板增殖区细胞在CRI组排列紊乱，细胞柱细胞数量少[（2.71±1.10）个/HP比（7.68±1.32）个/HP，P<0.001]；CRI组细胞初级纤毛表达率较高[（35.53±7.41）%比（18.31±5.12）%，P<0.001]。与假手术组比较，CRI组体外培养生长板软骨细胞24 h增殖率较低[（11.38±6.10）%比（24.35±8.46）%，P=0.001]，细胞初级纤毛表达率较高[（60.12±7.86）%比（32.17±8.97）%，P<0.001]，细胞初级纤毛长度较长[（3.54±1.61）μm比（1.96±0.82）μm，P=0.012]，IFT88蛋白表达量较高（0.47±0.23比0.17±0.10，P=0.001）。 结论： CRI幼鼠胫骨生长板增殖区软骨细胞初级纤毛表达率增高，细胞增殖率降低，生长板发育受限。.
Keywords: Epiphyses; Growth plate; Primary cilia; Renal insufficiency, chronic.