Chang C J, Sun C H, Liaw L H, Berns M W, Nelson J S
Chang Gung Memorial Hospital, Chang Gung Medical College, Taipei, Taiwan.
Lasers Surg Med. 1999;24(3):178-86. doi: 10.1002/(sici)1096-9101(1999)24:3<178::aid-lsm2>3.0.co;2-w.
The objective of the present study was to evaluate the feasibility of photodynamic therapy (PDT) for complicated hemangiomas. The photosensitizing activities of 5-aminolevulinic acid (5-ALA) and Photofrin were evaluated in vitro with human dermal microvascular endothelial cells (MEC) and in vivo with the chicken cox comb.
STUDY DESIGN/MATERIALS AND METHODS: The in vitro absorption and photosensitizing activities of 5-ALA and Photofrin were examined in a MEC culture system. The percentages of MEC killed by different drug concentrations at a wavelength of 630 nm were measured by either live/dead or lactate dehydrogenase-released assays. Similarly, the in vivo biological activities of 5-ALA and Photofrin exposed to different total light dosages at 630 nm were studied by determining the amount of necrosis produced in chicken combs.
MEC incubated with 5-ALA at a concentration of 35 microg/ml and exposed to laser light at 630 nm at a power density of 100 mW/cm2 showed a 50% cell kill. MEC incubated with Photofrin at a concentration of 3.5 microg/ml and exposed to laser light at 630 nm at a power density of 100 mW/cm2 showed a 50% cell kill. Chicken combs that received 200 mg/kg of 5-ALA exposed to laser light at 630 nm at a power density of 100 mW/cm2 had an injury depth of 362.5+/-27.6 microm at histologic examination. Combs exposed to a power density of 100 or 120 mW/cm2 showed injury depths of 732.5+/-29.1 and 792.5+/-36.0 microm, respectively. Chicken combs that received 2.5 mg/kg of Photofrin exposed to laser light at 630 nm at a power density of 80 mW/cm2 had an injury depth of 535.6+/-22.3 microm at histologic examination. Combs exposed to a power density of 100 or 120 mW/cm2 showed injury depths of 795.8+/-32.5 and 805.2+/-49.1 microm, respectively.
Both 5-ALA and Photofrin have the capability to destroy MEC in vitro and vasculature in vivo. However, Photofrin achieved a higher degree of cell kill and tissue destruction at lower drug concentrations and at lower power densities.
本研究的目的是评估光动力疗法（PDT）治疗复杂性血管瘤的可行性。在体外用人真皮微血管内皮细胞（MEC）以及在体内用鸡鸡冠评估5-氨基酮戊酸（5-ALA）和光敏剂的光敏活性。
研究设计/材料与方法：在MEC培养系统中检测5-ALA和光敏剂的体外吸收及光敏活性。通过活/死检测法或乳酸脱氢酶释放检测法测定在630nm波长下不同药物浓度杀死的MEC百分比。同样，通过测定鸡鸡冠产生的坏死量来研究在630nm下暴露于不同总光剂量的5-ALA和光敏剂的体内生物学活性。
用浓度为35μg/ml的5-ALA孵育MEC，并在功率密度为100mW/cm²的630nm激光照射下，显示50%的细胞死亡。用浓度为3.5μg/ml的光敏剂孵育MEC，并在功率密度为100mW/cm²的630nm激光照射下，显示50%的细胞死亡。接受200mg/kg的5-ALA并在功率密度为100mW/cm²的630nm激光照射下的鸡鸡冠，组织学检查显示损伤深度为362.5±27.6μm。暴露于功率密度为100或120mW/cm²的鸡冠，损伤深度分别为732.5±29.1和792.5±36.0μm。接受2.5mg/kg光敏剂并在功率密度为80mW/cm²的630nm激光照射下的鸡鸡冠，组织学检查显示损伤深度为535.6±22.3μm。暴露于功率密度为100或120mW/cm²的鸡冠，损伤深度分别为795.8±32.5和805.2±49.1μm。
5-ALA和光敏剂在体外均有破坏MEC的能力，在体内均有破坏脉管系统的能力。然而，光敏剂在较低药物浓度和较低功率密度下能实现更高程度的细胞杀伤和组织破坏。
