Morphology of the liver of the brook lamprey, Lampetra lamottenii before and during infection with the nematode, Truttaedacnitis stelmioides, hepatocytes, sinusoids, and perisinusoidal cells.
Routine light microscopy and transmission and scanning electron microscopy were used to describe and compare the livers of larval lampreys, Lampetra lamottenii before and during infection of the bile ducts by the nematode, Truttaedacnitis stelmioides. The hepatocytes of uninfected animals differ from other lamprey species in that they contain abundant glycogen, smooth endoplasmic reticulum (SER), and lipoprotein indicating that the liver may be involved in glucose metabolism. Infestation of the biliary tree by T. stelmioides coincides with alterations to the hepatocytes. These changes include dilation of the bile canaliculi, smooth endoplasmic reticulum (SER), rough endoplasmic reticulum (RER), and Golgi apparatus, swollen mitochondria in cells showing a high degree of hypertrophy, and an abundance of dense bodies. Following infection, the sinusoidal lumina became dilated and contain a moderate electron-dense precipitate, an abundance of melanomacrophages, lipocytes, and mononuclear cells. There is also a widening of the fenestrae of the sinusoidal endothelium following infection. Many of the changes in hepatocytes and sinusoids following parasite infections closely resemble those observed in hepatocytes in various pathologies and following experimental bile duct ligation and, therefore, are likely a consequence of increased biliary pressure due to bile duct obstruction.
Eng
F
F
Department of Zoology, University of Toronto, Ontario, Canada.
Youson
J H
JH
D000818:Animals; D001664:Biliverdine / Q000097:blood; D002779:Cholestasis / Q000209:etiology; D003593:Cytoplasm / Q000648:ultrastructure; D006003:Glycogen / Q000378:metabolism; D007798:Lampreys / Q000469:parasitology*; D007814:Larva / Q000469:parasitology; D008099:Liver / Q000469:parasitology* / Q000648:ultrastructure; D009349:Nematode Infections / Q000097:blood / Q000469:parasitology*
D006003:Glycogen; D001664:Biliverdine