title: The self-regulating synapse: a functional role for the co-existence of neuroactive substances.
abstract: Although the co-localizations of neuroactive substances, such as transmitters and peptides, in identified neurons is now a common histochemical phenomenon, the physiological roles and functional significance of such co-existence are largely unknown. Using the vertebrate retina as a model for the central nervous system, we have examined the relationship between co-existence and co-function. We propose here that the co-localization of neuroactive substances in a synaptic terminal provides the structural configuration to ensure the co-release of two or more predetermined substances into the same synaptic cleft, resulting in the capability of the presynaptic neuron to stringently regulate its own activities and output.
mesh_terms: D000818:Animals; D001345:Autoradiography; D002397:Catfishes; D002645:Chickens; D004745:Enkephalins / Q000502:physiology*; D006054:Goldfish; D009474:Neurons / Q000502:physiology; D012160:Retina / Q000502:physiology*; D013569:Synapses / Q000502:physiology*; D009435:Synaptic Transmission; D005680:gamma-Aminobutyric Acid / Q000502:physiology*
chemical_list: D004745:Enkephalins; D005680:gamma-Aminobutyric Acid