Hepatic stellate cell in the cell body store vitamin A as retinol ester. The function and role of quiescent hepatic stellate cells is unclear. Recent evidence suggests a role as a liver-resident antigen-presenting cell, presenting lipid antigens to and stimulating proliferation of NKT cells. When the liver is damaged, stellate cells can change into an "activated" state. The activated stellate cell is characterized by proliferation, contractility, and chemotaxis. This state of the stellate cell is the main source of extracellular matrix production in liver injury. This attribute makes it a key factor in the pathophysiology of the liver. The amount of stored vitamin
Organ of Zuckerkandl Organ of Zuckerkandl The organ of Zuckerkandl is a chromaffin body derived from neural crest located at the bifurcation of the aorta or at the origin of the inferior mesenteric artery. It can be the source of a paraganglioma. The term para-aortic body is also sometimes used to describe it, as it usually arises near the abdominal aorta, but this term can be the source of confusion, because the term "corpora paraaortica" is also used to describe the aortic body, which arises near the thoracic aorta. This diffuse group of neuroendocrine sympathetic fibres was first described by Emil Zuckerkandl, a