Expression of interleukin-6, c-fos, and zif268 mRNAs in rat ischemic cortex.
The expression of interleukin-6 (IL-6) mRNA in the focal ischemic rat cortex was studied by means of Northern hybridization. IL-6 mRNA was induced after permanent occlusion of the middle cerebral artery, reached a significant level at 3 h, and peaked at 12 h, i.e., approximately 10-fold increase in the ischemic zone compared with the nonischemic cortex or sham-operated controls. The increased IL-6 mRNA was elevated for at least 24 h. Low levels of IL-6 mRNA were detected in sham-operated rats or in the contralateral nonischemic cortex. The expression of c-fos and zif268 mRNAs, two early response genes, was rapid (increased by 1 h postischemia) and transient (returned to basal levels by 24 and 12 h, respectively), clearly having different kinetic patterns from that of IL-6 mRNA. The early response kinetic pattern of c-fos and zif268 mRNAs in focal ischemia suggests their transcriptional regulatory roles in response to ischemic insult, while the delayed induction pattern of IL-6 mRNA suggests a role for this pleiotropic cytokine in the inflammatory response to the focal ischemic damage of the brain.
Wang
X
X
Department of Cardiovascular Pharmacology, SmithKline Beecham Pharmaceuticals, King of Prussia, Pennsylvania 19406.
Yue
T L
TL
Young
P R
PR
Barone
F C
FC
Feuerstein
G Z
GZ
D000818:Animals; D015152:Blotting, Northern; D002540:Cerebral Cortex / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000235:genetics*; D051766:Early Growth Response Protein 1; D015870:Gene Expression; D016762:Genes, fos; D017874:Immediate-Early Proteins; D015850:Interleukin-6 / Q000235:genetics*; D002546:Ischemic Attack, Transient / Q000378:metabolism*; D007700:Kinetics; D012333:RNA, Messenger / Q000378:metabolism*; D051381:Rats; D011918:Rats, Inbred SHR; D014157:Transcription Factors / Q000235:genetics*; D016335:Zinc Fingers
D004268:DNA-Binding Proteins; D051766:Early Growth Response Protein 1; C486110:Egr1 protein, rat; D017874:Immediate-Early Proteins; D015850:Interleukin-6; D012333:RNA, Messenger; D014157:Transcription Factors