Summary
The spatial distribution and fine structure of the lymphatic vessels within the thymic lobules of normal and hydrocortisone-injected mice were studied by light- and electron microscopy. The lymphatic vessels of the cortex and medulla of normal thymus are irregularly shaped spaces closely associated with branches of the intralobular artery and vein. The overall distribution of these vessels in the greatly involuted thymus of hydrocortisone-treated mice is essentially the same as in the normal thymus. The wall of the lymphatic vessels consists of only a layer of endothelial cells supported by underlying reticular cells. The luminal surface of the endothelial cell is smooth, but trabecular processes are often seen. There are three morphological types of intercellular contacts between contiguous cells, namely, end-to-end, overlapping and interdigitating. The lymphatic vessel has anchoring filaments and collagen fibrils, but a basal lamina is either absent, or if present, is discontinuous. This is in contrast to the continuous basal lamina of the venule. The perivascular space surrounding the postcapillary venule opens into a terminal lymphatic vessel at the cortico-medullary junction and in the medulla. Lymphocytes are seen penetrating the lymphatic endothelium, particularly in acutely involuted thymuses. These findings suggest that the intralobular lymphatic vessels may originate from the vacuities that surround the postcapillary venules, and the lymphatic system may function as a pathway for the migration of lymphocytes into or out of the lymphatic circulation.
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References
Bargmann W (1943) Der Feinbau des Thymus. In: Handbuch der Mikroskopischen Anatomie der Menschen. Springer, Berlin Heidelberg New York, Vol. VI, Section 4, pp 113–119
Dunn TB (1954) Normal and pathologic anatomy of the reticular tissue in laboratory mice, with a classification and discussion of the neoplasmas. J Natl Cancer Inst 14:1281–1433
Hammar JA (1936) Die normal-morphologische Thymusforschung im letzten Vierteljahrhundert, Analyse und Synthese. VI. Die Lymphagefässe. Johann Ambrosius Barth Verlag, Leipzig, pp 320–327
Hoepke H, Peter H (1936) Das Verhalten des Igelthymus bei saurer und basischer Ernährung. Z Mikrosk Anat Forsch 39:263–314
Hoepke H, Spanier T (1939) Die Wirkung basischer und saurer Ernährung auf das Lymphgewebe der weißen Ratte. Z Mikrosk Anat Forsch 46:542–583
Hokazono K, Miyoshi M (1984) Scanningand transmission electron-microscopic study of lymphatic vessels in the splenic white pulp of the macaque monkey. Cell Tissue Res 237:1–6
Hwang WS, Ho TY, Luk SC, Simon GT (1974) Ultrastructure of the rat thymus. A transmission, scanning electron microscope, and morphometric study. Lab Invest 31:473–487
Kato S, Schoefl GI (1987) The vasculature of the guinea-pig thymus: Topographic studies by light and electron microscopy. Arch Histol Jpn 50:299–314
Kato S, Schoefl GI (1988) The microvasculature of the normal and involuted mouse thymus: Light and electron microscopic study. Acta Anat (in press)
Kotani M, Kawakita M, Yamashita A, Horii I (1966) Lymphatic drainage of thymocytes to the circulation in the guinea pig. Blood 27:511–520
Kotani M, Kwakita M, Fukanogi M, Yamashita A, Seiki K, Horii I (1967) The passage of thymic lymphocytes to the circulation in the rat. Okajimas Fol Anat Jpn 43:61–71
Murakami T (1974) A revised tannic-osmium method for noncoated scanning electron microscope specimens. Arch Histol Jpn 36:189–193
Omori H (1973) Finer distribution of the lymph vessels in the thymus. Acta Anat Nipp 48:315–329 (in Japanese with English abstract)
Pereira G, Clermont Y (1971) Distribution of cell web-containing epihtelial reticular cells in the rat thymus. Anat Rec 169:613–626
Smith C (1955) Studies on the thymus of the mammal. VIII Intrathymic lymphatic vessels. Anat Rec 122:173–179
Ushiki T (1986) Scanning electron-microscopic study of the rat thymus with special reference to cell types and migration of lymphocytes into the general circulation. Cell Tissue Res 244:285–298
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Kato, S. Intralobular lymphatic vessels and their relationship to blood vessels in the mouse thymus. Cell Tissue Res. 253, 181–187 (1988). https://doi.org/10.1007/BF00221753
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DOI: https://doi.org/10.1007/BF00221753