Pathways of lymph flow to and from the medulla of lymph nodes in sheep
Heath, T.J.; Spalding, H.J.
Journal of Anatomy 155: 177-188
1987
ISSN/ISBN: 0021-8782 PMID: 3503048 Document Number: 298431
Lymph pathways to and from the medulla in sheep lymph nodes were studied with Microfil casts, and with light and electron microscopy. It was found that medullary sinuses are continuous with penetrating afferent lymphatics, and with trabecular and tubular sinuses which penetrate through the cortex. Tubular sinuses are often associated with blood vessels, and they appear to be important in the transport of lymphocytes. The subcapsular sinus is continuous over the cortex and the medulla, although trabecular and reticular processes appear to restrict the flow of afferent lymph to the subcapsular sinus over the medulla. Lymph leaves the medulla through up to 100 or more initial efferent lymphatics some only 60 um across. Almost all of these arise from sinuses adjacent to the capsule lining the hilus. Some efferents remain associated with the capsule for a short distance whereas others, especially in nodes with a deep hilar depression, leave immediately at an angle of 30-90.degree.