Kanamasa K, Ishida N, Kato H, Sakamoto S, Nakabayashi T, Otani N, Ishikawa K, Katori R
First Department of Internal Medicine, Kinki University School of Medicine, Osaka, Japan.
Jpn Circ J. 1996 Nov;60(11):889-94. doi: 10.1253/jcj.60.889.
The purpose of this study was to clarify whether continuous infusion of recombinant tissue plasminogen activator (rtPA) prevents intimal hyperplasia at the site of arterial injury. Forty-three Kurosawa and Kusanagi hypercholesterolemic (KHC) rabbits which underwent balloon angioplasty of the right common iliac artery were randomly divided into 2 groups; rtPA for 7 days (n = 29) and untreated (n = 14). The former group was subdivided into a high-dose group (n = 15) (2 mg/kg per day continuously for 7 days after 3 mg/kg for 4h) and a low-dose group (n = 14) (0.6 mg/kg per day for 7 days after 0.6 mg/kg for 4 h). Balloon angioplasty was performed with a 2.5-mm balloon (3 x 60-sec, 6-atm inflations at 60-sec intervals) 1 h after the initiation of rtPA infusion via an ear vein. The iliac arteries of the rabbits were histologically studied at 28 days. The cross-sectional areas of the intima, media, and adventitia were calculated at the site of intimal hyperplasia. The intimal cross-sectional area was 0.07 +/- 0.11 (mean +/- SD) mm2 for the high-dose rtPA group and 0.11 +/- 0.07 mm2 for the low-dose rtPA group, and both of these values were significantly less than that for the control group (0.57 +/- 0.21 mm2 p < 0.01). The ratio of the intimal to medial cross-sectional area was significantly (p < 0.01) lower for the rtPA groups than for the control group (high-dose rtPA; 0.10 +/- 0.13, low-dose rtPA; 0.21 +/- 0.19, control; 1.25 +/- 0.55). In conclusion, continuous infusion of rtPA for 7 days prevented intimal hyperplasia after balloon injury.
本研究的目的是阐明持续输注重组组织型纤溶酶原激活剂（rtPA）是否能预防动脉损伤部位的内膜增生。43只接受右髂总动脉球囊血管成形术的黑泽和草柳高胆固醇血症（KHC）兔被随机分为2组；rtPA治疗7天组（n = 29）和未治疗组（n = 14）。前一组又分为高剂量组（n = 15）（在3mg/kg持续4小时后，每天2mg/kg持续7天）和低剂量组（n = 14）（在0.6mg/kg持续4小时后，每天0.6mg/kg持续7天）。通过耳静脉在开始输注rtPA 1小时后，用2.5mm球囊进行球囊血管成形术（3次，每次60秒，以60秒间隔6个大气压充气）。在28天时对兔的髂动脉进行组织学研究。在内膜增生部位计算内膜、中膜和外膜的横截面积。高剂量rtPA组的内膜横截面积为0.07±0.11（平均值±标准差）mm²，低剂量rtPA组为0.11±0.07mm²，这两个值均显著低于对照组（0.57±0.21mm²，p < 0.01）。rtPA组内膜与中膜横截面积之比显著低于对照组（p < 0.01）（高剂量rtPA组；0.10±0.13，低剂量rtPA组；0.21±0.19，对照组；1.25±0.55）。总之，持续输注rtPA 7天可预防球囊损伤后的内膜增生。
