Immunohistochemical demonstration of interleukin-1 beta induced changes in acute-phase proteins and albumin in rat liver.
Interleukin-1 beta is a potent mediator of the acute-phase response. However, the effects of interleukin-1 beta administration on the topic in vivo production of acute-phase proteins and albumin are so far not well understood. Overnight fasted rats were subcutaneously injected with 0.2 mL 0.9% NaCl (control group) or 6.25 micrograms recombinant human interleukin-1 beta, and rectal temperature was measured at intervals up to 48 h. Livers were perfused-fixed in vivo prior to injection (base-line), and at 9, 24, and 48 h following the interleukin-1 beta injection. Fibrinogen, orosomucoid (alpha 1-acid glycoprotein) and albumin were immunostained using a streptavidin-biotin-immunoperoxidase technique. Rectal temperature peaked 5 h after the single interleukin-1 beta injection, and fell gradually to base-line values by 24 h. Prior to injection only a few hepatocytes, randomly scattered throughout the liver lobule, stained positive for fibrinogen and orosomucoid. In contrast, all hepatocytes stained uniformly positive for fibrinogen and orosomucoid 9 h after interleukin-1 beta injection, whereas at 24 h a predominant centrilobular staining pattern occurred. Due to fasting, albumin positive hepatocytes were already reduced at base-line in both groups. Interleukin-1 beta induced a further significant loss of albumin positive cells in the periportal zone (35 +/- 21%) at 9 h when compared with controls (58 +/- 11%, p = 0.037). In conclusion, subcutaneous interleukin-1 beta (probably by stimulation of interleukin-6) strongly induces fibrinogen and orosomucoid expression in rat liver, and suppresses immunohistochemically stainable albumin in a heterogenous way, mainly in the periportal zone.
Department of Medicine, University of Berne, Inselspital, Switzerland.
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PE
Ballmer
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R
Imoberdorf
J
J
Zbären
D000209:Acute-Phase Proteins / Q000096:biosynthesis*; D000418:Albumins / Q000032:analysis / Q000378:metabolism*; D000818:Animals; D001831:Body Temperature / Q000187:drug effects; D005340:Fibrinogen / Q000032:analysis; D006801:Humans; D007150:Immunohistochemistry; D007375:Interleukin-1 / Q000494:pharmacology*; D008099:Liver / Q000737:chemistry / Q000187:drug effects* / Q000378:metabolism; D008297:Male; D009961:Orosomucoid / Q000032:analysis; D051381:Rats; D011919:Rats, Inbred Strains; D012007:Rectum; D013194:Staining and Labeling / Q000379:methods
D000209:Acute-Phase Proteins; D000418:Albumins; D007375:Interleukin-1; D009961:Orosomucoid; D005340:Fibrinogen