不同参数HMME-PDT对兔耳增生性瘢痕的生物效应

目的观察不同参数的血卟啉单甲醚-光动力学疗法（HMME-PDT）对兔耳增生性瘢痕的生物学效应，为临床应用HMME-PDT防治增生性瘢痕提供实验依据。方法建立兔耳增生性瘢痕模型后，将150个增生性瘢痕块随机分为HMME-PDT治疗组和对照组。PDT治疗组给予HMME10mg／kg，分别在给药后即刻、30min、1和3h行半导体激光照射，波长630nm，能量密度分别为5、10和20J／cm^2。观察瘢痕生长情况，术后28d取材行常规HE染色，计算各组瘢痕增生指数，分析HMME-PDT对瘢痕的影响。结果静脉注射HMME10mg／kg后，以功率密度为20mW／cm^2，能量密度为5J／cm^2的半导体激光在给药后即刻和30min照光时能对瘢痕增生块产生抑制效应，其中以时间间隔为30min时的作用更加显著，而能量密度为20J／cm^2的激光照射瘢痕增生指数仍然较高，甚至超过空白对照组。结论HMME-PDT对兔耳增生性瘢痕的生物学效应与光敏剂的剂量和激光照光时间、给药后至照光的时间间隔和能量密度密切相关。

Effect of HMME-PDT with Different Parameters on Hypertrophic Scarring in Rabbit Ear Model

Objective To investigate the effect of hematoporphyrin monomethyl ether-photodynamic therapy(HMME-PDT) with different parame- ters on hypertrophic scar in the rabbit ear. Methods The acute model of dermal hypertrophic scar in the rabbit ear was established.Totally 150 scar wounds were randomly divid- ed into 2 groups:the experimental group received HMME-PDT with different parameters,and the control group received no special treatment.Specimens were harvested from scar wounds on day 28 postoperation.Scar and hypertrophic index(HI) were observed by hematoxylin-eosin staining. Results Compared with the control group,HMME-PDT in the experimental group (photosensitizer dose 10 mg/kg,power density 20 mW/cm~2,energy fluence 5 J/cm~2) reduced scar formation and decreased the HI. Conclusions HMME-PDT may play a role in inhibiting hypertrophic scarring in rabbit ear.The biological effect is determined by dose of photosensitizer,interval of photosensitizer injection and irradiation,power density and energy fluence.