TNF-ALPHA INCREASES THE FREQUENCY OF SPONTANEOUS MINIATURE SYNAPTIC CURRENTS IN CULTURED RAT HIPPOCAMPAL-NEURONS

Tumor necrosis factor-alpha (TNF-alpha) is a cytokine secreted by acti vated astrocytes and is known to alter evoked synaptic activity in sli ces of adult rat hippocampus. In this paper we show that TNF-alpha inc reases the frequency of spontaneous miniature synaptic currents in cul tured hippocampal neurons, acting at nanomolar concentrations. In addi tion, we show that the mRNA for the 55 kDa TNF-alpha receptor (TNF-R1) is detected in embryonic rat hippocampal cultures, as well as in acut ely dissected embryonic and adult rat hippocampi. Possible transductio n pathways mediating the TNF-alpha effect are discussed.