睾酮对去睾丸家兔骨密度及血清钙磷的影响

EFFECTS OF EXOGENOUS TESTOSTERONE ON BONE MINERAL DENSITY(BMD) AND PLASMA LEVELS OF SEX HORMONE AND CALCIUM,PHOSPHORUS IN ORCHIECTOMIZED RABBITS

目的 :观察去睾丸和睾酮补充对雄兔骨密度和血清钙、镁、磷的影响。方法 :周龄相同的雄性新西兰白兔随机分成对照组、去睾丸组和睾酮补充组 (去睾丸后肌注十一酸睾酮 )。同等条件下饲养 2 0周后测量各组兔全身骨密度、腰椎骨密度、股骨颈骨密度 ,并检测血清总睾酮 (TT)、雌二醇 (E2 ) ,脱氢表雄酮 (DHEA)水平以及血清钙 (Ca2 + )、游离钙([Ca2 + ]i)镁 (Mg2 + )、磷 (P)和碱性磷酸酶 (AKP)浓度。结果 :去睾丸组血清TT水平明显下降 (P <0 .0 1) ,睾酮补充组血清TT水平升高接近对照组 (P >0 .0 5 )。去睾丸组血清E2 和E2 /TT比明显高于对照组 (P <0 .0 1) ,睾酮补充组血清E2 和E2 /TT下降 ,接近对照组水平 (P均 >0 .0 5 )。与对照组相比 ,去睾丸组血清Ca2 + 、[Ca2 + ]i、Mg2 + 以及AKP浓度明显升高 (P均 <0 .0 1) ,睾酮补充组血清Ca2 + 、[Ca2 + ]i、Mg2 + 以及AKP浓度较去睾丸组低 ,接近对照组水平 (P >0 .0 5 )。股骨颈骨密度在去睾丸组明显低于对照组和睾酮补充组 (P <0 .0 1) ,而后两组无差别 (P >0 .0 5 )。结论 :去睾丸后雄兔血清TT明显下降 ,E2 和E2 /TT比以及Ca2 + 、[Ca2 + ]i、Mg2 + 和AKP浓度明显升高 ,骨密度显著下降 ,睾酮补充使上述异常明显改善。

Aim: To investigate the effects of testosterone on bone mineral density(BMD),plasma levels of sex hormone and calcium,phosphorus,and parathyroid hormone(PTH). Methods: Thirty 10 week old male rabbits were randomized into sham operated(SH),orchiectomized (ORX) and testosterone undecanoate replacement(TU) group. TU rabbits were injected with testosterone undecanoate in 10 orchiectomized rabbits and the remaining SH and ORX rabbits,vehicle only 20 weeks after initiation of the experiment,bone mineral density was measured with dual-energy X-ray bone densitometer. Blood was collected for determination of serum levels of total testosterone,estradiol,calcium,magnesium,phosphorus and alkaline phosphatase(AKP). Results: The serum levels of total testosterone and femond neck BMD decreased,serum levels of calcium,magnesium and AKP increased significantly in ORX rabbits,testosterone improved femond neck BMD and decreased serum levels of calcium,magnesium and AKP significantly in TU rabbits. Conclusion: The results of the present study indicate that ORX decrease serum testosterone and BMD,exogenous testosterone treatment can prevent osteoporosis in ORX rabbits.