Search results
Results from the WOW.Com Content Network
In histology (microscopic anatomy), the lobules of liver, or hepatic lobules, are small divisions of the liver defined at the microscopic scale. The hepatic lobule is a building block of the liver tissue, consisting of portal triads, hepatocytes arranged in linear cords between a capillary network, and a central vein.
The hepatocyte plates are one cell thick in mammals and two cells thick in the chicken. Sinusoids display a discontinuous, fenestrated endothelial cell lining. The endothelial cells have no basement membrane and are separated from the hepatocytes by the space of Disse, which drains lymph into the portal tract lymphatics. [citation needed]
Hepatocytes constitute about 80% of the cell population of the liver, with the other 20% being occupied by Kupffer cells, hepatic stellate cells, endothelial cells and mesothelial cells, which are not exactly characteristic of the liver, but are present in the liver samples. [2] Histologically speaking, hepatocytes have specific characteristics.
A liver sinusoid is a type of capillary known as a sinusoidal capillary, discontinuous capillary or sinusoid, that is similar to a fenestrated capillary, having discontinuous endothelium that serves as a location for mixing of the oxygen-rich blood from the hepatic artery and the nutrient-rich blood from the portal vein.
The fenestrae occupy 20% of the LSEC surface and are arranged in groups referred to as "sieve plates". [2] Filtering fluid between the sinusoidal lumen and the space of Disse, the fenestrae are crucial for lipoprotein traffic between the hepatocytes and the sinusoidal lumen. [3] The LSECs lack an organized basal lamina. [4]
GGT is a microsomal enzyme found in hepatocytes, biliary epithelial cells, renal tubules, pancreas, and intestines. It helps in glutathione metabolism by transporting peptides across the cell membrane. Much like ALP, GGT measurements are usually elevated if cholestasis is present. [10]
Piecemeal necrosis in liver aka interface hepatitis is necrosis of the limiting plates, by inflammatory cells. It may be identified as actual necrosis of cells or by irregularity of the limiting plates which is caused IOS's hepatocytes and replacement with inflammatory cells and/or fibrosis.
The proportion of AST to ALT in hepatocytes is about 2.5:1, but because AST is removed from serum by the liver sinusoidal cells twice as quickly (serum half-life t 1/2 = 18 hr) compared to ALT (t 1/2 = 36 hr), so the resulting serum levels of AST and ALT are about equal in healthy individuals, resulting in a normal AST/ALT ratio around 1.