Interleukin-1 inhibits NMDA-stimulated GnRH secretion: associated effects on the release of hypothalamic inhibitory amino acid neurotransmitters.
Immune system activation is often accompanied by alterations in the reproductive axis. Interleukin-1 (IL-1), a polypeptide cytokine, has been postulated as a chemical messenger between the immune and the neuroendocrine systems. Using superfused hypothalamic fragments explanted from intact male rats, we evaluated the effects of IL-1 (0. 5 and 5 nM) on basal and N-methyl-D-aspartate (NMDA)-stimulated release of gonadotropin-releasing hormone (GnRH), and the associated modifications in the output of inhibitory amino acid neurotransmitters involved in the control of GnRH secretion. IL-1 did not modify basal GnRH release, but markedly restrained the stimulatory effect of NMDA on GnRH secretion. gamma-Aminobutyric acid, glycine and taurine concentrations significantly increased in the superfusion medium only after pretreatment with the higher dose of IL-1 (p < 0.05). Our results indicate that this cytokine inhibits NMDA- stimulated GnRH release, affecting the activity and/or the release of hypothalamic excitatory and inhibitory amino acid neurotransmitters participating in the regulation of GnRH secretion.
Feleder
C
C
Departamento de Fisiología, Facultad de Medicina, Universidad de Buenos Aires, Argentina.
Arias
P
P
Refojo
D
D
Nacht
S
S
Moguilevsky
J
J
D000818:Animals; D018690:Excitatory Amino Acid Agonists / Q000494:pharmacology*; D005998:Glycine / Q000378:metabolism; D007987:Gonadotropin-Releasing Hormone / Q000378:metabolism*; D007033:Hypothalamus, Middle / Q000276:immunology / Q000378:metabolism*; D007375:Interleukin-1 / Q000494:pharmacology*; D008297:Male; D016202:N-Methylaspartate / Q000494:pharmacology*; D009433:Neural Inhibition / Q000187:drug effects / Q000276:immunology; D015213:Neuroimmunomodulation / Q000187:drug effects / Q000276:immunology; D011301:Preoptic Area / Q000276:immunology / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D013654:Taurine / Q000378:metabolism; D005680:gamma-Aminobutyric Acid / Q000378:metabolism*
D018690:Excitatory Amino Acid Agonists; D007375:Interleukin-1; D013654:Taurine; D007987:Gonadotropin-Releasing Hormone; D005680:gamma-Aminobutyric Acid; D016202:N-Methylaspartate; D005998:Glycine