The Effect Of Nitroglycerin And Verapamil For The Contents Of INOS ATP And TAN In Canine's Donor Lung Tissues

Objective: Add Nitroglycerin and Verapamil in low-potassium-dextran (LPD) solution, we observe the contents of iNOS,ATP and TAN in different lung tissues, and evaluate the protection effect.Method: Native-bred canines of either sex (weight 14-16 kg) were paired by weight. 20 canines served as donors and 20 canines each served as recipients for the lungs. We separate them into 4 groups, each groups has 5 pairs. (1)Control group, we only use LPD solution to protect the donor lung ; (2) Nitroglycerin group, we add Nitroglycerin in the LPD solution; (3) Verapamil group, we add Verapamil in the LPD solution ; (4) Experimental group, we add Nitroglycerin and Verapamil in the LPD solution.Anesthesia was induced by intramuscular injection of pentobarbital sodium(301ng/kg), then we put the endotracheal tube into the trachea. Animals were ventilated with a tidal volume of 15 ml/kg and a respiratory rate of 15-20 breaths/min at FiO2 of 1.0 with an animal ventilator.Donor Procedure: In the right-sided position, a left antero-lateral thoracotomy was performed through the fourth intercostal space. After incision of the mediastinal pleura and pericardium, upper and lower caval veins and right pulmonary artery were dissected free from surrounding tissues. Systemic heparinization (3mg/kg), was given by intravenously, then we ligate the upper and lower caval veins. Turn-off the ventilator, A cannula was inserted into right pulmonary artery and fixed by a tourniquet. The lungs of the different groups were flushed with different cold lung protection liquid(0-4℃) by gravitation, with a constant height of 40 cm H₂O ,The flushing procedure was started after an incision of the left auricle, thus permitting the effluent to emerge into the thorax. When the lungs turn into white and the effluent turn into clarification,we stop flushed with the cold lung protection liquid. The lungs were deflated and the heart-lung bloc was removed. Put the bloc into the cold lung protection liquid, the lungs were reinflated and the trachea was cross-clamped, cut, and submerged under the solution. The heart was dissected and the donor lung bloc was immersed in fresh cold lung protection liquid and stored for 6 hr at 0-4℃.Recipient Procedure: Single-lung transplantation was performed in the right-sided position, a left antero-lateral thoracotomy was performed through the fourth intercostal space. The mediastinal pleura and pericardium was incised and a tourniquet was placed around the left pulmonary artery. After pneumonectomy, heparin(1.5mg/kg) was administered intravenously, and implantation commenced with the bronchial anastomoses, followed by the pulmonary arterial and left atrial anastomoses. Before we open the right pulmonary artery, Prednisolone(80mg) was administered intravenously. The graft was ventilated and reperfusion started. The chest wall was closed with towel clamps.After 2 hr reperfusion, a potion of lung tissue was resected, we observe the contents of iNOS,ATP and TAN in different lung tissues.Results: (1)The content of iNOS: The contents of iNOS in contral group are higher than other groups(p＜0.05). The contents of iNOS in Experimental group are lower than group 2 and 3(p＜0.05).There is no obviously different between group 2 and 3(p＞0.05). (2)The content of ATP: The contents of ATP in contral group are lower than other groups(p＜0.05). The contents of iNOS in Experimental group are higher than group 2 and 3(p＜0.05).There is no obviously different between group 2 and 3(p＞0.05). (3) The content of TAN:The contents of TAN in contral group are lower than other groups(p＜0.05). The contents of TAN in Experimental group are higher than group 2 and 3(p＜0.05).There is no obviously different between group 2 and 3(p＞0.05).Conclusion: (1)The iow-potassium-dextran with Nitroglycerin or Verapamii can reduce the content of iNOS in the donor lung tissues, and the result is better when we add both Nitroglycerin and Verapamil in the LPD liquid .(2)The low-potassium-dextran with Nitroglycerin or Verapamil can improve the content of ATP and TAN in the donor lung tissues, and the result is better when we add both Nitroglycerin and Verapamil in the LPD liquid.