Transmisión sináptica-canales de calcio y liberación de neurotransmisore

Abstract

Neuronal communication in the nervous system is mediated, in the vast majority of animals, by chemical synaptic transmission. In most cases this junctional communication occurs via the release of a transmitter substance, from a presynaptic nerve terminal. This synaptic transmitter binds post-synaptic receptors and results in a postsynaptic response on the target cell. Such release of transmitter from the presynaptic terminal appears to be universally triggered by a transient increase of intracellular calcium at the release site. This transient increase in calcium, is mostly brought about by the activation of voltage gated calcium channels (VGCC) which result in a Ca2+ influx into the presynaptic cytosol that triggers synaptic vesicle fusion and neurotransmitter release. Methodology: Databases such as Medline, Pubmed and Columbia University Library ejournals were consulted, in order to find articles published from January 1990 to November 2004. Conclusions: During the last decade significant advances have been achieved in the molecular and genetics of voltage gated channels. The integration of this knowledge with functional neurophysiology and clinical neurology is only starting.