去卵巢和抗骨质疏松干预后大鼠尿脱氧吡啶啉的变化

目的观察大鼠去卵巢及予以不同的干预后尿脱氧吡啶啉/肌酐比率(urinarydeoxypyridinolinecrosslink/creatinine,UDpd/Cr)的变化,了解其在骨质疏松的诊断和治疗中的应用价值。方法将40只Wister大鼠于6月龄时行去卵巢手术(OVX,n=32)和假手术(Sham,n=8)。手术后6周分别予以不同的干预如下:OVX组(Ovx,n=8)和Sham组不做干预;雌激素干预组(O+E,n=9)予以17β雌二醇20μg/(kg·d),皮下注射;英卡膦酸钠干预组(O+C,n=7)予以Cimadronate0.2mg/(kg·d),经胃肠给药。手术后14周将大鼠处死,处死前收集24h尿液和血液测定血清及尿液中生化指标;处死后留取右侧股骨标本,进行股骨外周定量CT骨密度及股骨远端凹入实验生物力学测定。结果OVX组大鼠的骨吸收指标UDpd/Cr比Sham组增加了133.3%(P<0.01),OVX组大鼠尿钙/肌酐比率亦有增加,但与Sham组相比差异无显著性(P>0.05)。雌激素和英卡膦酸钠干预组UDpd/Cr比OVX组显著降低,分别减少了54.6%和51.8%(P均<0.01),并与Sham组接近。UDpd/Cr与骨量、骨密度及骨生物力学等指标的相关分析表明,其与以上指标之间存在显著负相关。结论UDpd/Cr是敏感的骨吸收指标,在OVX和予以雌激素、二膦酸盐干预后均有显著变化,其改变与骨密度及骨骼力学特性的改变密切相关。

Changes of urinary deoxypyridinoline crosslink/creatinine in rats after ovariectomy and anti-osteoporotic intervention

OBJECTIVE: To observe the changes of urinary deoxypyridinoline crosslink/creatinine (UDpd/Cr) in rats after OVX and intervention by estrogen and bisphosphonate and investigate the possible application of deoxypyridinoline in osteoporosis diagnosis and treatment. METHODS: 40 female 6-month-old virginal Wistar rats were divided into 5 groups, ovariectomized or sham ovariectomized. (1) Ovxb (n = 8): sacrificed at 6 weeks after OVX; (2) Sham (n = 8): sham ovariectomized; (3) Ovxe (n = 8): sacrificed at 14 weeks after OVX; (4) O + E (n = 9):OVX + 17 beta estradiol [20 micrograms/(kg.d) ih]; (5) O + C (n = 7):OVX + cimadronate [0.2 mg/(kg.d)]; Treatment started 6 weeks after OVX and lasted 8 weeks. Rats in group 2-5 were sacrificed at 14 weeks after OVX. Urinary and serum biochemical parameters were measured, pQCT scanning of femur, bone biomechanical test in femur were determined. RESULTS: OVX resulted in increasing of UDpd/Cr 133.3% (P < 0.01). The ratio of UCa/Cr also increased in OVX groups but without any significant compared with Sham (P > 0.05). UDpd/Cr were reduced by 54.6% and 51.8% (P < 0.01) in O + E, O + C group respectively compared with Ovxe. The significant negative correlationships were found between UDpd/Cr and bone mass, BMD and biomechanic characteristics. CONCLUSIONS: UDpd/Cr ratio is a sensitive bone resorption marker, a marked changes were observed when the rats ovariectomized or treated with estradiol and cimadronate. There were best correlation between UDpd/Cr and bone mineral density and bone biomechanic characteristics. It is fair to apply UDpd/Cr ratio for osteoporosis diagnosis and treatment.