Moderate hypothermia alters interleukin-6 and interleukin-1alpha reactions in ischemic brain in mice.
Female C57BL/6 mice were decapitated and their brains were removed and cultured at either 37 or 33 degrees C for 48 h to investigate whether or not moderate hypothermia alters the cytokine reactions in the ischemic brain. The interleukin-6 and interleukin-1alpha levels in the culture media were significantly elevated in a time-dependent manner. The interleukin-6 levels after the incubation at 33 degrees C were significantly lower than those at 37 degrees C. The interleukin-1alpha levels at 33 degrees C were significantly higher than those at 37 degrees C. The interleukin-1alpha levels incubated with interleukin-6 antibody were significantly higher than those without IL-6 antibody. At 37 degrees C, the mRNA expression of interleukin-6 was observed from 2 to 48 h after incubation, but the same expression of interleukin-1alpha was only detected until 12 h. Accordingly, the ischemic brain incubated at 33 degrees C showed a decreased interleukin-6 production in comparison with that at 37 degrees C and the level of interleukin-6 showed negative feedback for the production of interleukin-1alpha. The temperature should, therefore, be carefully considered when evaluating the cytokine reaction for cerebral ischemia.
Yanagawa
Youichi
Y
Department of Traumatology and Critical Care Medicine, National Defense Medical College, Tokorozawa, Saitama, Japan. yokkom@f7.dion.ne.jp
Kawakami
Masato
M
Okada
Yoshiaki
Y
D000818:Animals; D001921:Brain / Q000378:metabolism*; D002545:Brain Ischemia / Q000503:physiopathology*; D004195:Disease Models, Animal; D005260:Female; D007036:Hypothermia, Induced; D007375:Interleukin-1 / Q000032:analysis / Q000096:biosynthesis*; D015850:Interleukin-6 / Q000032:analysis / Q000096:biosynthesis*; D051379:Mice; D008810:Mice, Inbred C57BL; D012333:RNA, Messenger / Q000032:analysis; D013696:Temperature
D007375:Interleukin-1; D015850:Interleukin-6; D012333:RNA, Messenger