title: Interleukin-1 (IL-1) receptor type I mediates anorexia but not adipsia induced by centrally administered IL-1beta.
abstract: IL-1beta induces anorexia and adipsia. Here, we report that intracerebroventricular (ICV) pretreatment with an antisense (but not sense) phosphothio-oligodeoxynucleotide to the IL-1 receptor type I (IL-1RI, 1.28 microg or 239 pmol twice daily for 3.5 days before IL-1beta plus antisense) inhibits the anorexia, but not the adipsia induced by the ICV administration of 2.0 ng IL-1beta/rat (a dose that yields estimated pathophysiological concentrations in the cerebrospinal fluid). The mean 2 h food intake decrease in response to IL-1beta was 5.6% (n = 10) in the antisense- and 43% in the sense (n = 9)-treated groups; the mean 2 h water intake decrease was 40% in the antisense- and 39% in the sense-treated groups. The intraperitoneal administration of IL-1RI antisense, in doses equivalent to those administered centrally, had no effect on the anorexic effect induced by ICV administered IL-1beta; this indicates a direct action in the central nervous system. The results suggest that: i) IL-1RI is involved in the short-term anorexigenic, but not the adipsogenic effect induced by centrally administered IL-1beta; and ii) the approach presented using antisense strategies is applicable to study the molecular basis of IL-1 mediated behaviors.
authors.affiliation: Division of Molecular Biology, School of Life and Health Sciences, University of Delaware, Newark 19716-2590, USA.
authors.forename: G
authors.initials: G
authors.lastname: Sonti
authors.forename: M C
authors.initials: MC
authors.lastname: Flynn
authors.forename: C R
authors.initials: CR
authors.lastname: Plata-Salamán
mesh_terms: D000818:Animals; D001066:Appetite / Q000187:drug effects / Q000502:physiology*; D001921:Brain / Q000187:drug effects / Q000502:physiology; D004326:Drinking / Q000187:drug effects / Q000502:physiology*; D004435:Eating / Q000187:drug effects / Q000502:physiology*; D006815:Hunger / Q000187:drug effects / Q000502:physiology*; D007276:Injections, Intraventricular; D007375:Interleukin-1 / Q000494:pharmacology*; D008297:Male; D051381:Rats; D017208:Rats, Wistar; D017472:Receptors, Interleukin-1 / Q000187:drug effects / Q000502:physiology*
chemical_list: D007375:Interleukin-1; D017472:Receptors, Interleukin-1