Interleukin-1 modulates GABAergic and glutamatergic function in brain.

Interleukin-1 is a polypeptide cytokine involved in the acute-phase response. We examined the effects of IL-1 on the major inhibitory and excitatory neurotransmitter systems in brain mediated by GABA and glutamate, respectively. IL-1 enhanced the effects of GABA as determined by GABA-dependent chloride uptake at 1 and 10 ng/ml in cortical synaptoneurosomes. This effect was attenuated by pretreatment with the IL-1 receptor antagonist. Neither IL-6 nor TNF was effective in this system. IL-1 decreased the effect of NMDA and glycine on intracellular calcium concentrations in cultured chick cortical neurons in both the presence and absence of the endogenous polyamine spermine. This effect was attenuated by pretreatment with the AMPA/kainate antagonist CNQX. These data indicate that IL-1 modulates both inhibitory and excitatory neurotransmitter function in brain.