The Present work is carried out in the hope to investigate the changes on the Pulmonary Parenchyma influenced ,by the pulmonary vessels and nerves in normal adult dogs. The animals were divided into following 7 groups, and the changes were observed anatomically and histopathologically in the period of I to 170 days.
The left bronchial arterial supply was studied in 37cases. 34 cases (92%) of them revealed a single bronchial arterial system, whereas only 3 cases (8%) demonstrated double arterial supplies. Among the former group, 22 cases(64.7%) disclosed the artery being originated from the third intercostal artery, 8 cases(23.5%) from the second and 2 cases from the fifth intercostal artery. The right bronchial artery studied in .28 cases showed a single brondhial arterial supply in 24cases (86 %), 12 cases(50%) among them, the artery was demonstrated to arise from the second intercostal artery
Group 1. Ligation of bronchial artery only.
There were several complications of pulmonary hemorrhage, edema, congestion, bronchopneumonia, pleuritis and atelectasis in 22 cases, however, these changes were quite focal and mild in degree in all cases. Reparative processes and uneventful gradual recovery were readily observed as the experiment was prolonged to 30 days, and the lungs were essentially histologically normal in appearance in animals survived more than 50 days. (between 50 to 100 days.)
Group 2. Ligation of pulmonary artery only.
No specific histopathological changes were present in the pulmonary parenchyma except for a mild degree of transitory complications.
Group 3. Ligation of both pulmonary and bronchial arteries.
Six animals were observed between 8 to 18 days after the ligations. All of them disclosed pulm
onary infarcts, resulting in permanent damage to the parenchyma. There were secondary changes of
pulmonary congestion, parencymal hemorrhage, atelectasis and bronchopneumonia. Group 4. Ligation and section of bronchus.
All of the ligated and sectioned cases revealed diffuse fusiform dilatation of the entire bronchial tree, evidence of excessive amount of mucin secretion in the distal bronchi, plugging of mucinous material in the proximal segments and foci of squamous metaplasia of the bronchial mucosa of the proximal segments. Group 5-7. Section of one or both vagus and sympathetic nerves,
No specific histopathological changes were noted in these groups except for a mild degree of bronchopneumonia present.
The results of the experiment show that a single ligation of each bronchial or pulmonary artery, sect ions of vagus and sympathetic nerves gave temporal. and mechanical reactions to the pulmonary parenchyma, but legations of both pulmonary and bronchial arteries, and ligation and section of the bronchi revealed a permanent parenchymal damage.
Clinical significance´s of obstruction of the bronchi are reconsidered, and the possibility of transplantation of the lungs is suggested.
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