Modulation of the neurotransmitter release in rat cerebellar neurons by GRO beta.

We report here that, in cultured cerebellar granule cells, the CXC chemokine GRObeta stimulates the signaling pathway of the extracellular signal-regulated kinases, and enhances both evoked and spontaneous postsynaptic currents in patch clamped Purkinje neurons from rat cerebellar slices. The GRObeta-induced enhancement of the excitatory post-synaptic currents evoked by stimulating the parallel fibres is blocked by the inhibitor of the extracellular signal-regulated kinases pathway PD98059, which also reduces both basal frequency of spontaneous post-synaptic currents and mean amplitude of evoked excitatory post-synaptic currents. Our results suggest that GRObeta modulates neurotransmitter release in the cerebellum through the activation of the extracellular signal-regulated kinases pathway.