富血小板血浆对大鼠跟腱断裂早期愈合的影响

目的富血小板血浆(platelet-rich plasma,PRP)具有促进损伤组织修复作用。通过观察PRP局部注射对大鼠跟腱断裂早期愈合的影响,为临床应用提供实验依据。方法 SPF级SD大鼠46只,雌雄不限,体重190～240 g。取10只大鼠心脏动脉血制备PRP及贫血小板血浆(platelet-poor plasma,PPP);其余36只随机分为3组(n=12),分别为空白对照组、PPP组及PRP组。大鼠制备双侧跟腱断裂模型后,PPP组和PRP组跟腱周围局部对应注射PPP及PRP,每侧100μL,每周1次至处死;空白对照组不作处理。术后观察大鼠一般情况,于1、2、3、4周取双侧跟腱,行大体、组织学及免疫组织化学染色观察,测量新生跟腱Ⅰ型胶原纤维含量;并于4周行生物力学测试。结果大鼠均存活至实验完成。随着时间延长,各组大鼠跟腱水肿逐渐减退,滑动性逐渐改善;术后3周内各组跟腱粘连逐渐加重,4周时减轻,1、4周时各组跟腱粘连程度分级差异均无统计学意义(P>0.05)。术后1周PRP组炎性细胞浸润、毛细血管及胶原纤维增殖较空白对照组、PPP组明显,之后炎性反应及毛细血管生成逐渐减少。各时间点各组均可见Ⅰ型胶原纤维阳性表达,术后1、2、3周PRP组Ⅰ型胶原纤维阳性密度值多于空白对照组和PPP组(P<0.05),4周时3组差异无统计学意义(P>0.05)。生物力学测试:术后4周3组跟腱最大滑动距离比较,差异均无统计学意义(P>0.05);PRP组跟腱弹性模量及最大抗拉力明显高于空白对照组及PPP组(P<0.05)。结论大鼠跟腱断裂早期于断端周围注射PRP能促进跟腱愈合。

Effect of platelet-rich plasma injection on early healing of Achilles tendon rupture in rats

Objective Platelet-rich plasma(PRP) can promote wound healing.To observe the effect of PRP injection on the early healing of rat’s Achilles tendon rupture so as to provide the experimental basis for clinical practice.Methods Forty-six Sprague Dawley rats were included in this experiment,female or male and weighing 190-240 g.PRP and platelet-poor plasma(PPP) were prepared from the heart arterial blood of 10 rats;other 36 rats were made the models of Achilles tendon rupture,and were randomly divided into 3 groups(control group,PPP group,and PRP group),12 rats for each group.In PPP and PRP groups,PPP and PRP of 100 μL were injected around the tendons once a week,respectively;in the control group,nothing was injected.The tendon tissue sample was harvested at 1,2,3,and 4 weeks after operation for morphology,histology,and immunohistochemistry observations.The content of collagen type I fibers also was measured.Specimens of each group were obtained for biomechanical test at 4 weeks.Results All the animals survived till the end of the experiment.Tendon edema gradually decreased and sliding improved with time.The tendon adhesion increased steadily from 1 week to 3 weeks postoperatively,and it was relieved at 4 weeks in 3 groups.There was no significant difference in the grading of tendon adhesion among 3 groups at 1 week and at 4 weeks(P > 0.05),respectively.The inflammatory cell infiltration,angiogenesis,and collagen fibers were more in PRP group than in PPP group and control group at 1 week;with time,inflammatory cell infiltration and angiogenesis gradually decreased.Positive staining of collagen type I fibers was observed at 1-4 weeks postoperatively in 3 groups.The positive density of collagen type I fibers in group PRP was significantly higher than that in control group and PPP group at 1,2,and 3 weeks(P < 0.05),but no significant difference was found among 3 groups at 4 weeks(P > 0.05).The biomechanical tests showed that there was no significant difference in the maximal gliding excursion among 3 groups at 4 weeks postoperatively(P > 0.05);the elasticity modulus and the ultimate tensile strength of PRP group were significantly higher than those of control group and PPP group at 4 weeks(P < 0.05).Conclusion PRP injection can improve the healing of Achilles tendon in early repair of rat’s Achilles tendon rupture.