Interleukin-1 beta augments release of norepinephrine, dopamine, and serotonin in the rat anterior hypothalamus.
We investigated the effects of interleukin-1 beta (IL-1 beta), administered directly into the rat anterior hypothalamus (AHY), on monoamine release in the same region by using a brain microdialysis technique and an HPLC-electrochemical detection system. First, to study the local effects of IL-1 beta, we used a microdialysis probe equipped with a microinjection tube for administering IL-1 beta in the same region into which the probe had been inserted. IL-1 beta (1 ng) injected directly into the AHY elicited release of norepinephrine (NE), dopamine (DA), and 5-HT, as well as increases in their metabolites, 4-hydroxy-3-methoxyphenylglycol, 3,4-dihydroxyphenylacetic acid, 4-hydroxy-3-methoxyphenylacetic acid, and 5-hydroxyindole-3-acetic acid, in the AHY. Vehicle alone exerted no effect on monoamine release. Although the elevated levels of NE and DA persisted for more than 6 hr after injection of IL-1 beta, the elevated levels of 5-HT were transient. Second, in order to investigate whether this effect of IL-1 beta is a direct action in the AHY, we performed in vitro experiments using hypothalamus slices. IL-1 beta (0.1 and 1 nM) increased the levels of each monoamine released from hypothalamic slices in a dose-dependent manner. These findings suggest that IL-1 beta acts directly on the hypothalamus to induce release of NE, DA, and 5-HT. Third, the roles of prostaglandins (PGs) in NE release in the AHY elicited by direct injection of IL-1 beta were examined.(ABSTRACT TRUNCATED AT 250 WORDS)
Department of Neuro-psychiatry, Keio University School of Medicine, Tokyo, Japan.
F
F
Shintani
S
S
Kanba
T
T
Nakaki
M
M
Nibuya
N
N
Kinoshita
E
E
Suzuki
G
G
Yagi
R
R
Kato
M
M
Asai
D015121:6-Ketoprostaglandin F1 alpha / Q000378:metabolism; D000324:Adrenocorticotropic Hormone / Q000097:blood; D000818:Animals; D002851:Chromatography, High Pressure Liquid; D003346:Corticotropin-Releasing Hormone / Q000378:metabolism; D003907:Dexamethasone / Q000494:pharmacology; D003956:Dialysis; D004298:Dopamine / Q000378:metabolism*; D007032:Hypothalamus, Anterior / Q000378:metabolism*; D007213:Indomethacin / Q000494:pharmacology; D007375:Interleukin-1 / Q000008:administration & dosage / Q000494:pharmacology*; D007700:Kinetics; D008297:Male; D008845:Microinjections; D009638:Norepinephrine / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D012701:Serotonin / Q000378:metabolism*
D007375:Interleukin-1; D012701:Serotonin; D015121:6-Ketoprostaglandin F1 alpha; D003907:Dexamethasone; D000324:Adrenocorticotropic Hormone; D003346:Corticotropin-Releasing Hormone; D004298:Dopamine; D009638:Norepinephrine; D007213:Indomethacin