Naloxone antagonizes behavioural and ECoG effects induced by systemic or intracerebral administration of some lymphokines.
Rat interferon, alpha-interferon, interleukin-2 and recombinant interleukin-2 microinjected into the third cerebral ventricle produced in rats typical behavioural sedation and/or sleep and ECoG synchronization while beta-interferon produced no behavioural sleep and ECoG synchronization. A slight sedation was observed after highest dose of beta-interferon only. During sleep induced by these lymphokines a dose-dependent increase in total voltage power as well as in the 0.5-3, 4-7 and 12-16 Hz frequency bands was observed. Much lower doses were required to produce similar behavioural and ECoG spectrum power effects after microinfusion of interferons and interleukin-2 into the locus coeruleus. No significant behavioural and ECoG changes were obtained after microinfusion of the same doses of interferons and interleukin-2 into other areas of the brain (caudate nucleus, dorsal hippocampus, substantia nigra-pars compacta-, ventromedial hypothalamus). The behavioural and ECoG effects of alpha-interferon, rat interferon and interleukin-2 were blocked in animals pretreated with naloxone. These results are consistent with the hypothesis that the behavioural and ECoG effects of these lymphokines are mediated at locus coeruleus level via a stimulation of opiate receptors.
De Sarro
G B
GB
Istituto di Farmacologia, Facoltà di Medicina di Catanzaro, Università degli Studi, Reggio Calabria, Italy.
Nisticò
G
G
D000818:Animals; D004305:Dose-Response Relationship, Drug; D004569:Electroencephalography / Q000187:drug effects*; D007275:Injections, Intravenous; D007276:Injections, Intraventricular; D008125:Locus Coeruleus / Q000187:drug effects* / Q000502:physiology; D008222:Lymphokines / Q000008:administration & dosage / Q000037:antagonists & inhibitors* / Q000494:pharmacology; D008297:Male; D009270:Naloxone / Q000494:pharmacology*; D051381:Rats; D011919:Rats, Inbred Strains; D011994:Recombinant Proteins / Q000494:pharmacology; D012890:Sleep / Q000187:drug effects
D008222:Lymphokines; D011994:Recombinant Proteins; D009270:Naloxone