The release of immunoreactive interleukin-1 beta from rat hypothalamic explants is modulated by neurotransmitters and corticotropin-releasing hormone.
Both constitutive and inducible interleukin-1 (IL-1) gene expressions have been described in the central nervous system, the former being associated with immunoreactive IL-1 neurons in human and rat hypothalami. While most studies have focused on the role of IL-1 as a mediator of pathological events in the brain, the cytokine of neuronal origin might also be involved in the regulation of physiological processes. In this study we used a previously validated technique to investigate the effects of classical neurotransmitters and the hypophysiotropic peptide corticotropin-releasing hormone (CRH) on the release of immunoreactive (ir) IL-1 beta from acute rat hypothalamic explants. We found that basal irIL-1 beta secretion is significantly inhibited by acetylcholine and histamine and increased by dopamine, while dexamethasone, IL-4 and IL-10 have no effect. Moreover, cytokine release is dose-dependently increased by CRH. Such effects of the neurotransmitters and CRH are observed in short-term incubation experiments, indicating that a pre-formed pool of hypothalamic IL-1 beta is involved. These findings also suggest that the interaction between IL-1, neurotransmitters and neuropeptides might play a role in the physiological regulation of such processes as body temperature, food intake and the control of hypothalamic-hypophyseal axes.
Tringali
G
G
Institute of Pharmacology, Catholic University Medical School, Rome, Italy.
Mirtella
A
A
Mancuso
C
C
Guerriero
G
G
Preziosi
P
P
Navarra
P
P
D000109:Acetylcholine / Q000494:pharmacology; D000818:Animals; D003346:Corticotropin-Releasing Hormone / Q000494:pharmacology*; D004298:Dopamine / Q000494:pharmacology; D006632:Histamine / Q000494:pharmacology; D007031:Hypothalamus / Q000187:drug effects* / Q000378:metabolism; D007375:Interleukin-1 / Q000378:metabolism*; D008297:Male; D018377:Neurotransmitter Agents / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar
D007375:Interleukin-1; D018377:Neurotransmitter Agents; D006632:Histamine; D003346:Corticotropin-Releasing Hormone; D000109:Acetylcholine; D004298:Dopamine