The effect of neuropeptide Y on voltage-sensitive Ca2+ channels

Neuropeptide Y (NPY) (50-1000 nM) failed to modify basal or K(+)-stimulated Ca2+ influx in cortical or hippocampal synaptosomes from rat brain, whereas the voltage-sensitive Ca2+ channel (VSCC) blocker Cd2+ (50 microM) caused major inhibition. In cortical synaptosomes from chicken brain NPY (1.0 microM) failed to modify, whereas omega-conotoxin GV1A (0.1 microM) markedly inhibited Ca2+ influx. NPY does not appear to modify synaptosomal Ca2+ influx, however it may still affect VSCCs spatially distinct or 'upstream' from the nerve terminals.