Changes

<p>Follicles in the cortex of a stimulated node are larger and have a pale germinal centre. Activated [[Lymphocytes#B cells|B cells]] differentiate into plasma and memory cells. Plasma cells migrate to the medullary cords and produce immunoglobulins.</p>

<p>Follicles in the cortex of a stimulated node are larger and have a pale germinal centre. Activated [[Lymphocytes#B cells|B cells]] differentiate into plasma and memory cells. Plasma cells migrate to the medullary cords and produce immunoglobulins.</p>

==High endothelial venules==

==[[High Endothelial Venules]]==

<p> High endothelial venules (HEV) are composed of cuboidal/columnar epithelium and are the major route for lymphocytes to enter the node. HEV contain a large number of aquaporin-1 channels allowing for a large uptake of water which in turn drives lymph flow through the cortex. This fluid is then returned direct to the bloodstream. The venules are the source of most of the node's [[Lymphocytes#T cells|T cells]] and [[Lymphocytes#B cells|B cells]] and express selectins (receptors for lymphocytes primed with antigens).</p>

==Function==

==Function==