Brain-derived neurotrophic factor (BDNF) promotes the survival of neuronal populations that are all located or connected to the central nervous system. BDNF is a major regulator of synaptic transmission and plasticity at adult synapses in many regions of the CNS. The versatility of BDNF is emphasized by its contribution to a range of adaptive neuronal responses including long-term potentiation (LTP), long-term depression (LTD), certain forms of short-term synaptic plasticity, as well as homeostatic regulation of intrinsic neuronal e, Xenopus/Amphibian,citability.