In vivo and electron microscopic observations of the responses of the hepatic sinusoid to interleukin-1.
Interleukin-1 (IL-1), which is produced by Kupffer cells and sinusoidal endothelial cells, may play an important role in immunological and microvascular responses to a variety of stimuli in the liver. The responses of the hepatic microvasculature including phagocytic activity of sinusoidal lining cells to IL-1 alpha were examined in C57Bl/6 mice in vivo and using electron microscopy. One hour after recombinant mouse IL-1 alpha was injected at doses of 80 U, the low dose group, and 800 U, the high dose group, the phagocytic activity of sinusoidal lining cells showed significant differences between the two treated groups and between the two groups and the controls. In the low dose group, the numbers of sinusoids containing blood flow and of leukocytes adhering to the sinusoidal lining remained unchanged, but the former decreased and the latter increased significantly in the high dose group. Ultrastructurally, Kupffer cells that phagocytosed latex particles appeared to have decreased in number while the sinusoidal endothelial cells became phagocytic. A considerable number of leukocytes were seen adhering to the sinusoidal endothelium. These findings demonstrate that IL-1 alpha not only elicited sticking and plugging by leukocytes in sinusoids but also activated phagocytic functions in the hepatic sinusoidal endothelial cells. These endothelial responses are similar to those seen following FV3 virus infection, chronic administration of ethanol, or a combination of cocaine and ethanol, or during extracorporal perfusion, suggesting that IL-1 may participate in these responses.
Nishida
J
J
Department of Cell Biology and Anatomy, College of Medicine, University of Arizona, Tucson 85724, USA.
McDonnell
D
D
McCuskey
M K
MK
Ekataksin
W
W
McCuskey
R S
RS
D000704:Analysis of Variance; D000818:Animals; D002448:Cell Adhesion / Q000187:drug effects; D004730:Endothelium, Vascular / Q000166:cytology / Q000187:drug effects* / Q000648:ultrastructure; D007375:Interleukin-1 / Q000494:pharmacology*; D007728:Kupffer Cells / Q000187:drug effects / Q000648:ultrastructure; D008099:Liver / Q000098:blood supply* / Q000166:cytology / Q000276:immunology; D008102:Liver Circulation / Q000187:drug effects*; D008213:Lymphocyte Activation; D008297:Male; D051379:Mice; D008815:Mice, Inbred Strains; D008833:Microcirculation / Q000187:drug effects; D008854:Microscopy, Electron; D010586:Phagocytes / Q000187:drug effects* / Q000648:ultrastructure; D010587:Phagocytosis / Q000187:drug effects; D011994:Recombinant Proteins / Q000494:pharmacology
D007375:Interleukin-1; D011994:Recombinant Proteins