Résumé
The immune system is an important system to perform defend function,and the lymph node is an important component in this system.There are a variety of immune cells in lymph nodes to produce specific immune responses against invading pathogens.In these immune responses,the high endothelial venule is not only important to maintain the structure of lymph node,but also an important channel for lymphocyte homing.Therefore,studies on its development in lymph nodes and changes in lymph node metastasis of malignant tumors will provide great benefits for clinical diagnosis and treatment.
Résumé
Two methyl methacrylate corrosion casts prepared from the intra-microvascular system of human brain-stem were used for the observation of morphological features of the system. Arterioles, venules and capillaries have their own morphological features respectively, so it is not difficult to distinguish one from others. Besides different forms of impressions formed by the endothelial cells nuclei on the surface of larger arterioles and venules, there are semicir cular impressions formed by the smooth muscle cells on the surface of larger venules and the majority of larger venules take a looplike shape on their way to pass forward. All these characteristics could be used to distinguish the larger venules. There are anastomoses between arterioles and between venules, with some A-V communicating branches between arterioles and venules.
Résumé
The microvasculature of the lung of three humans was studied with the replicascanning electron microscopic method. The pulmonary arteriole belongs to microvasculature at the level of the respiratory bronchiole and gives out some side branches to the alveoli. The diameter of the arteriole is about 30-50 ?m. The arteriole divided into terminal arterioles, which accompanied with primary alveolar ducts. The diameter of the terminal arteriole is about 10-20 ?m, 17.35?1.62 ?m in average (n=30). There are obvious imprints of smooth muscles and endothelial nuclei on the surface of the casts of arteriole and terminal arteriole. The diameter of the alveolar capillary is 5.87?0.90 ?m in average (n=500). The proportion of the capillary area arround the alveole is 66?1.4%. There are two patterns of capillary network, i. e. long mesh and round mesh in type. The diameter of the mesh is (9.24?2.02)?(5.65?1.40) and 5.75?0.84 ?m, respectively. The distance of the mesh center is 17.13?1.74 ?m (long) and 11.52?1.12 ?m (short) in long mesh, and 11.63?0.88 ?m in round mesh. The capillary network of the long mesh located at the entrance and the base of the alveoli; and the round mesh in the area between them. The metaarteriole supplying the alveoli enters the alveoli at their entrance and thev venule draining the alveoli at their base. The distance between them is about 330 ?m.According to the microvascular architecture, the pulmonary microvasculature may be divided into three ordered units: i. e. the alveolar, the alveolar duct, and the respiratory bronchiolar units.
Résumé
The microvascutature of the adrenal medulla in the rats and mice were studied by scanning electron microscopy of vascular replicas.There are portal venules between the adrenal cortex and medulla,which are the side branches of the collecting venules of the adrenal cortex and break into capillaries at the adrenal medulla.The adrenal medulla in mice is mainly supplied by these portal venules,and in a rat adrenal medulla,there are also 5—8 medullar arterioles besides the portal venules.Ring-like constrictions appear to be the characters of sphincter at the ending parts of the portal venules,the branches of the medullar arterioles,the collecting venules,and the medullar venules which drain the medullar capillaries as well.The authors believe that the adrenal cortex controls the medulla by the way of the portal venules.
Résumé
Objective To study the distribution of proteoglycan(PG) in high endothelial venules(HEVs), inquire into regulate role of proteoglycans for lymphocyte homing. Methods With cationic iron colloid solution staining enzyme sequence blocked method, the distribution of different PG in lymphocytes inside the HEVs, endothelial cells and basement membranes were observed under the light microscope and electron microscope. Results The basement membrane of HEVs and the lymphocytes adjacent basement membranes were strongly positive staining, they could be blocked by hyaluronidase, heparinase and chondroitinase. under the electron microscope, the colloid granules were mainly distributed inside or outside the basement membranes and in the traversing or traversed basement membranes lymphocyte membranes. The endothelial cells, the lymphocytes traversing endothelium and the lymphocytes inside the HEVs were negtive staining.Conclusion The PG that distributed in the basement membranes of HEVs and the membranes of lymphocyte traversing basement membranes were mainly heparin sulfate proteoglycan and chondroitin sulfate proteoglycan and hyaluoronic acid, they may play an important role in the homing lymphocytes traversed basement membranes.