Expression of tissue factor in rabbit pulmonary artery in an acute pulmonary embolism model

Abstract

BACKGROUND: Tissue factor (TF) is the initiation factor of the extrinsic coagulation pathway, and plays a critical role in the process of thrombosis. This study aimed to investigate the expression of TF and to explore their clinical effect on the pulmonary artery after acute pulmonary thromboembolism.METHODS: Thirty-four Japanese white rabbits (Level II animals) supplied by Tianjin Medical University were randomly assigned into: group A, specimens of the pulmonary artery taken 3 hours after pulmonary embolism (n=8); group B, specimens of the pulmonary artery taken 8 hours after pulmonary embolism (n=8); group C, specimens of the pulmonary artery taken 24 hours after pulmonary embolism (n=8); and control group, pseudo-operations performed without injection of autologous blood clots (n=10). The animal model of pulmonary thrombo-embolism was established by injection of autologous blood clots into the jugular vein through a 5F catheter, and was confi rmed by digital subtraction angiography. The mRNA expression of TF in different parts of the pulmonary artery was accessed by RT-PCR. The q test was used if there was a signifi cant difference in a given continuous variable among the three groups assessed by ANOVA. The experiment equipment was supplied by the State Key Laboratory of Experimental Hematology, Institute of Hematology and Blood Diseases Hospital, the Chinese Academy of Medical Sciences and Peking Union Medical College. RESULTS:The TF expression in the specimen adjacent to emboli was stable at 3, 8 or 24 hours after embolism. The mRNA expression of TF at 3 and 8 hours after embolism was lower in the specimens taken from the distal end of the morbid pulmonary artery than those adjacent to emboli. While at 24 hours after embolism, there were similar mRNA levels in specimens either adjacent or distal to emboli. CONCLUSION:The high level of TF expression in pulmonary artery tissue adjacent to emboli could lead to locally increased coagulation activity, indicating the necessity of initiating anticoagulation treatment as soon as possible after acute pulmonary embolism.

Changes of fibrinolytic system in thrombolytic resuscitation of pulmonary thromboembolism‐induced cardiac arrest model

“…It eventually forms thrombin, resulting in fibrin deposition and platelet activation to form thrombus. Zhang et al 15 found that after 3 and 8 hours of embolization, TF expression of the pulmonary artery distal to embolization was significantly lower than that of the pulmonary artery and normal pulmonary artery. There was no significant difference in TF expression between the embolized pulmonary arteries and normal pulmonary arteries.…”

Risk Assessment in Chinese Hospitalized Patients Comparing the Padua and Caprini Scoring Algorithms

“…The inflammatory response-mediated complex agglutination cascade results in impaired vascular cells, which can induce thrombus along with activation of inflammatory cells resulting in an inflammation–thrombosis cycle. 24 –26 One study included 220 (62.1%) patients in the medical ward and 134 (37.9%) in the surgical ward. Patients with respiratory infection had the highest incidence of high or highest Caprini risk (78.1%).…”

Rodent models of pulmonary embolism and chronic thromboembolic pulmonary hypertension

“…In some studies, allogeneic [ 32 , 33 ] or even xenogeneic blood [ 34 , 35 , 36 ] has been used for ex vivo preparation of thromboemboli. These models are produced in animals of various species, including mice [ 37 , 38 , 39 ], rats [ 37 , 40 , 41 ], hamsters [ 35 , 42 , 43 ], and rabbits [ 44 , 45 , 46 ] ( Table 2 ).…”

“…TE administration – jugular vein 7 days – [ 47 ] 38 Rabbits Autologous thrombi – 2–4 mm diameter, 7–10 mm length 2 pcs in vitro addition of thrombin Changes in tissue factor expression in rabbits during acute PE Blood sampling – marginal auricular vein. TE administration – jugular vein 3, 8 and 24 h – [ 44 ] 39 Rabbits Autologous thrombi – 2 × 20 mm – – Study of FIIa enzyme fibrinolytic activity from the Agkistrodon acutus venom in acute PE TE administration – through a catheter in the RV 2 h – [ 45 ] 40 Rabbits Autologous thrombi – – Thrombi from 10 ml or 1 ml of blood – Comparison of the traditional iodine-containing contrast effectiveness and contrast agent based on the liposomal pool of blood in PE Blood sampling –auricular vein. TE administration – ental jugular vein 270 min – [ 58 ] Note: RV — right ventricular, TE — thromboemboli, PE — pulmonary embolism, CTEPH — chronic thromboembolic pulmonary hypertension, СаСl 2 — calcium chloride, 125 I — iodine-125 labelled, MCP-1 — monocyte attractant protein - 1, SD — Sprague-Dawley, Cop.…”