Insulin-like growth factor I and pulmonary hypertension induced by continuous air embolization in sheep.
Insulin-like growth factor I and pulmonary hypertension induced by continuous air embolization in sheep.
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绵羊持续空气栓塞诱导的胰岛素样生长因子 I 和肺动脉高压。
DOI：
10.1165/ajrcmb/6.1.82
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发表时间：
1992
影响因子：
6.4
通讯作者：
Meyrick,B
中科院分区：
文献类型：
--
作者：
Perkett,EA;Badesch,DB;Roessler,MK;Stenmark,KR;Meyrick,B
材料和方法如前所述，将绵羊模型留置导尿管放置在一周岁的绵羊体内。在全身麻醉下，行双侧开胸手术，插入肺动脉导管和左房导管，插入尾部纵隔结节的传出管。同时，通过颈部切开将导管插入颈静脉和颈动脉。基线肺活检组织是在手术时获得的，如前所述(26)。在开始实验之前，绵羊被允许恢复7天。经颈静脉置入Swan-Ganz热稀释导管。在开始空气栓塞术前2天监测肺动脉、左房和全身压力，并测定心输出量。如前所述，持续空气栓塞术进入肺动脉循环的速度足以维持肺血管阻力增加2-3倍(24)。每天进行血流动力学监测，以评估动物的状态，并在必要时调整空气栓塞率。6只动物接受空气栓塞术，2只动物作为对照。在基线(第0天)通过EDTA收集肺淋巴，离心，上清液在-700℃下冷冻，在空气栓塞术的12天中每天收集额外的样本。对三只绵羊的血浆样本也进行了采集和冷冻，以供将来化验。淋巴和血浆样本的总蛋白浓度用自动改良的双缩二脲方法测定(27)。在12天的空气栓塞后，绵羊被过量的巴比妥酸盐杀死。立即打开胸腔，肺部充气至30厘米水的压力。夹闭肺外周，取出肺组织，置于4%多聚甲醛磷酸盐缓冲液(PBS)中，5分钟后取出。固定过夜后，将组织置于70%酒精中。然后，组织通过升级醇脱水，在二甲苯中清除，并用石蜡包埋。
Materials and MethodsSheep Model Indwelling catheters were placed in yearling sheep as previously described (25). Under general anesthesia, bilateral thoracotomies were performed for insertion of pulmonary arterial and left atrial catheters and for cannulation of the efferent duct of the caudal mediastinal node. At the same time, catheters were inserted into the jugular vein and carotid artery through an incision in the neck. Baseline lung biopsy tissue was obtained at the time of surgery as previously described (26). The sheep were allowed to recover for 7 days before beginning the experiments. A Swan-Ganz thermodilution catheter was introduced by way of the jugular vein. Pulmonary arterial, left atrial, and systemic pressures were monitored and cardiac output was determined on 2 separate days before beginning air embolization. Continuous air embolization was administered into the pulmonary arterial circulation as previously described at a rate sufficient to sustain a 2-to 3-fold increase in pulmonary vascular resistance (24). Hemodynamic monitoring was performed daily to assess the status of the animals and adjust the rate of air embolization if necessary. Six animals received air embolization, and two animals served as controls. Lung lymph was collected at baseline (day 0) over EDTA, centrifuged, and the supernatant was frozen at-700 C. Additional samples were collected daily throughout the 12 days of air embolization. In three sheep, plasma samples were also collected and frozen for future assay. Total protein concentration in lymph and plasma samples was determined using an automated modified biuret method (27). After 12 days of air embolization, the sheep were killed with an overdose of barbiturate. The chest was opened immediately, and the lungs were inflated to a pressure of 30 cm H2O. A piece of peripheral lung was clamped, excised, and placed in 4% paraformaldehyde in phosphate-buffered saline (PBS) at 40 C. After 5 min, the clamp was removed. After overnight fixation, the tissue was placed in 70% alcohol. The tissue was then dehydrated through ascending alcohols, cleared in xylene, and embedded with paraffin wax.