Renal interleukin-1 expression during endotoxemia and gram-negative septicemia in conscious rats.
Endotoxin-induced cytokines such as interleukin-1 (IL-1) and tumor necrosis factor (TNF) are thought to contribute to the proinflammatory effects of endotoxin in gram-negative infections. Using a conscious rat model of sepsis, induced by intravenous challenge with LD95 doses of endotoxin (n = 24) or live Escherichia coli (E. coli) (n = 24), we examined frozen sections of kidney at various intervals for evidence of IL-1 alpha and TNF alpha expression. A transient glomerular endothelial IL-1 alpha expression was demonstrated at 30 and 90 min after initiation of the sepsis in both endotoxin and E. coli-treated animals using immunohistochemistry. The endothelial IL-1 alpha expression as determined by immunohistochemistry occurred at the same time as IL-1 alpha mRNA expression, as determined by Northern blot analysis. The glomerular endothelial IL-1 alpha expression coincided with a slight but significant increase in the number of the glomerular polymorphonuclear leukocytes as identified by naphthol AS-D chloroacetate esterase enzyme histochemical reaction. Glomerular endothelial IL-1 alpha expression was virtually absent by 180 and 360 min. No TNF alpha expression was detected in the renal tissues at any time interval. Neither alpha-naphthyl acetate esterase-positive nor acid phosphatase-positive monocytes/macrophages were identified in the glomeruli. Our findings provide direct in vivo evidence that the IL-1 alpha gene product is expressed locally in the kidney by glomerular endothelial cells in this septic rat model.
Laszik
Z
Z
Department of Pathology, University of Oklahoma Health Sciences Center, Oklahoma City.
Nadasdy
T
T
Johnson
L D
LD
Lerner
M R
MR
Brackett
D
D
Silva
F G
FG
D000818:Animals; D016470:Bacteremia / Q000378:metabolism*; D004731:Endotoxins / Q000097:blood*; D004927:Escherichia coli Infections / Q000378:metabolism*; D016905:Gram-Negative Bacterial Infections / Q000378:metabolism*; D007150:Immunohistochemistry; D007375:Interleukin-1 / Q000235:genetics / Q000378:metabolism*; D007668:Kidney / Q000378:metabolism*; D008297:Male; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D014115:Toxemia / Q000378:metabolism; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism
D004731:Endotoxins; D007375:Interleukin-1; D012333:RNA, Messenger; D014409:Tumor Necrosis Factor-alpha