Induction of interleukin-1 beta mRNA in the hypothalamus following subcutaneous injections of formalin into the rat hind paws.
The induction of interleukin-1 beta (IL-1 beta) mRNA in the rat brain following subcutaneous injection of formalin into the hind paws was investigated by in situ hydridization. IL-1 beta mRNA was markedly induced in the hypothalamus after the injection of formalin into both hind paws. On the other hand, IL-1 beta mRNA was scarcely observed in the hypothalamus of saline-injected control rats. The type of cells expressing IL-1 beta mRNA was likely glia because their nuclei were densely stained by Cresyl violet and were relatively small. The present results suggest that IL-1 beta mRNA is induced in the glial cells of the hypothalamus by persistent pain which is caused by formalin injection.
Yabuuchi
K
K
Department of Pharmacology, Faculty of Pharmaceutical Sciences, Kyoto University, Japan.
Maruta
E
E
Minami
M
M
Satoh
M
M
D000818:Animals; D005557:Formaldehyde / Q000494:pharmacology*; D006614:Hindlimb / Q000187:drug effects*; D007031:Hypothalamus / Q000187:drug effects*; D017403:In Situ Hybridization; D007375:Interleukin-1 / Q000378:metabolism*; D008297:Male; D012333:RNA, Messenger / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley
D007375:Interleukin-1; D012333:RNA, Messenger; D005557:Formaldehyde