Study On The Stereostucture And Microvasculature Of The Bronchial Arteries In Pig

In order to study the three-dimensional distribution and microvasculature of bronchial arteries in pig,we study on the origin of bronchial artery,the characteristic of branch,the regularity of distribution,the way of blood backflow and the microvasculature of bronchial arteries by independent casting metheod,combined casting method,ink and gelatin slicing method and scanning electron microscopy.The results are demonstrated as fellows.A method have been established for making macro and micro bronchial arterial casting by using ABS casting technology. The integral independent bronchial artery cast specimens and the combined cast specimens of bronchial artery were obtained in this study..2.The experiment have ascertained the three-dimensional structure of porcine bronchial artery.The pig has 1 to 3 bronchial arteries, 1 of them most. The bronchial artery stem diameter of 1 branch type was significantly larger than the 2 branch type(P<0.05). The opening of bronchial artery is mainly based on the single opening in the thoracic aorta and the two opening only accounts for 28.6%.The 1 type of bronchial artery is divided into ascending posterior branch,right anterior descending,anterior descending and left anterior descending branch at the hilum.When bronchial artery enter the hilum of lung,the trunk of bronchial artery respectively.issued right apical lobe bronchial artery, left anterior dorsal bronchial artery, left main bronchus artery, left anterior descending artery, right anterior dorsal bronchial bronchi artery and right main bronchus artery.Each segmental bronchi have 1 to 3 bronchial arteries and the 2 branch type is the most.Two bronchial arteries parallel serpentine extend along the bronchi.The number of bronchial artery branch of apical lobe,middle lobe and accessory lobe segment bronchi is constant and there is no significant difference between the branch.The number of bronchial artery branch of diaphragmatic lobe segment bronchi is not constant and the dorsal,ventral,medial and lateral segment bronchial artery system have 3 branch type, 4 type.The dorsal and lateral bronchial have single branch type, two branches, three branches and four type branching type.. The bronchial artery in 4 ways supply the lung pleura, and bronchial artery anastomosis occurred widely in various forms. Pulmonary vein is one of the main drainage channels of bronchial artery.3.The experiment have ascertained the distribution characteristics of the pleural surface of bronchial artery microvascular.After comparatively analyzed the pleural tissue slice with ink and gelatin and ABS scanning electron microscope results,we found that bronchial artery can form two layer vascular network,which are the pleural surface and the subpleural vascular network.The characteristics of the pleural surface vascular network is as follows:The vascularnetwork is relatively sparse, coarse meshes, polygonal mesh, diameter thick,and has extensive formation of vascular anastomosis.The diameter of micro vascular trunk is relatively large and the majority of blood vessel diameter are between 30 and 60 um.The characteristics of the subpleural vascular network is as follows:bronchial arteries from multiple sources form a layer of smooth, uniform size, dense grid of subpleural capillary network that the diameter is about8-10 um,the form of capillary meshes usually is irregular 5-7 shape, and the vascular anastomosis are formed between 4-6 mesh and each anastomosis.The extending path of the capillary network branch that bronchial artery formed has remarkable consistency in the pleura and the length and size of vessel have no significant difference.4.The experiment have ascertained the bronchial artery distribution in the bronchi.After comparatively observed ink and gelatin sections and scanning electron microscopy, we found that a small branch of BA in the lung can be distributed to the outer membrane, bronchial submucosa and lamina propria, and vascular network can be formed in lamina propria.The branches of bronchial arteries can covered the entire alveolar capillary network. Therefore, the bronchial artery is a major source of alveolar capillary network.5.The experiment have ascertained the microvascular distribution on the inner and outer surface of the bronchovascular set.The microvascular distribution of bronchial vascular network on the outer surface of the bronchovascular set is as follows:the trunk of bronchial artery send out many branches to the bronchial surface in the direction of the branch. The diameter of micro artery tube is between 100 um and 170 um, the diameter of capillary is about 8-10 um, and the difference of micro artery diameter size is significant. Micro artery is relatively straight line process, on the way from the levels of micro artery is relatively flat, the phenomenon of anastomosis is is less consistent, vascular network is relatively sparse. The microvascular distribution of bronchial vascular network sets on the inner surface of is as follows: the medial vascular network is smooth and dense, and the vascular network is composed of multiple layers.The microvascular network derived from the outer surface of the capillary structure at all levels.The vascular network regularity and consistency are relatively strong, but the difference of mesh size and shape are significant. The mesh form is varied, the diameter of mesh can reach 200 um,and the smallest mesh is only 8-15 um.