兔激素性股骨头坏死病程中肝脂肪酶改变的意义

Change of hepatic lipase and its meaning during the glucocorticoid- induced avascular necrosis of femoral head in rabbits

目的:探索激素性股骨头坏死(NFH)病程中肝脂肪酶(HL)的变化及其意义.方法:新西兰大白兔40只随机分为4组,A组:空白对照;B组:地塞米松;C组:地塞米松+丙酸睾酮;D组:丙酸睾酮.分别在给药的第0,1,3,5wk采血行三酰甘油(TG),总胆固醇(TCH),高密度脂蛋白(HDL)以及HL活性的检测.并于实验的第5,8wk分批处死实验对象,取股骨头标本行骨坏死指标的检测.结果:B,C组TG,TCH,HDL较A,D组明显升高,B组的HL活性下降,C组的HL活性较B组明显升高,D组较正常组高.B组第8wk镜下可见股骨头内脂肪细胞增多,骨细胞坏死空骨陷窝形成明显;但第5wk时改变轻微.C组也存在类似改变,但病变程度较轻.结论:激素性股骨头坏死病程中存在高脂血症、HL活性下降,给予HL活性增强剂可以改善血脂紊乱状态,并可以改善骨坏死的程度,延缓其进程.

AIM： To elucidate the change of hepatic lipase （HL） activity and its meaning during the glucocorticoid-induced avascular necrosis of the femoral head （NFH）. METHODS： Forty mature New Zealand white rabbits were randomly allocated to 4 groups： group A served as control; group B were given dexamethasone at a dose of 7.5 mg/kg iv per day for the 1 st week, then at a dose of 2.5 mg/kg im every other day; group C, given dexamethasone just as group B, were also given testosterone pro- pionate at a dose of 5 mg/kg im every 3 d at the same time; group D only received testosterone propionate supra citato. Just before and at the 1st, 3rd, 5th week of the experiment, 12-fasted blood samples were collected 15 rain after given heparin sodium （at a dose of 50 U/kg iv） to monitor plasma lipid and lipoprotein concentrations and HL activity. Objects were sacrificed in batch randomly and bilateral femoral head were collected to detect bone necrosis index at the 5th and 8th week of the experiment. RESULTS： Compared with group A and group D, the concentrations of TG, TCH and HDL in group B and C were much higher （especially in group B）; the HL activity decreased distinctively in group B,but reascended in group C. While compared with group A,the HL activity was higher in group D. At the end of the 8th week in group B, empty lacuna, increased adipocytes and osteocyte necrosis were extremely obvious; but during the 5th week, such changes were not so serious. Similar changes were also found in group C, but the changes were slight. CONCLUSION：Decrease of HL activity and hyperlipemia exist in the process of glucocorticoid-induced NFH, but hyperlipemia can be relieved when agents are given to upgrade HL activity,and such agents can improve NFH and delay its progression.