Developmental Changes in Calcium Channel Types Mediating Central Synaptic Transmission

摘要: Multiple types of high-voltage-activated Ca2+channels trigger neurotransmitter release at the mammalian central synapse. Among them, ω-conotoxin GVIA-sensitive N-type channels and ω-Aga-IVA-sensitive P/Q-type mediate fast synaptic transmission. However, most synapses, it is not known whether contributions different Ca2+ channel to transmission remain stable throughout postnatal development. We have addressed this question by testing type-specific blockers developing synapses. Our results indicate that contribute thalamic cerebellar IPSCs only transiently during early period predominantly mature transmission, as we reported previously brainstem auditory synapse formed calyx Held. In fact, currents directly recorded from calyceal presynaptic terminal were identified N-, P/Q-, R-types day 7 (P7) P10 but became P13. contrast EPSCs, persistently cerebral cortical EPSCs spinal months. Thus, in adult animals, mediated a subset synapses synergistically multiple other