THE RELEASE OF NEURAL TRANSMITTER SUBSTANCES

Factors Involved in the Release of Transmitter Substances at Mammalian Junctional Regions

Glial cell function: uptake of transmitter substances.

Rabbit-brain fractions enriched in neuronal cell bodies and in glial cells accumulated norepinephrine, serotonin, dopamine, and gamma-aminobutyric acid, substances believed to serve as neurotransmitters in the central nervous system. Both neurons and glia were able to concentrate the monoamine transmitters about 4-fold from a medium containing 0.1-1 muM concentrations. However, the glial-cell f...

Neural transmitter release: from quantal secretion to exocytosis and beyond..

First of all, let me thank you, Mr Chairman, and your Council for inviting me to give the Wallace Fenn Lecture on this great occasion. I have pleasant memories of my meetings with Wallace Fenn, whom I admired as a person and as a scientist. I had heard much about his achievements long before we met; I knew about him through our mutual friend and teacher, A.V. Hill, in whose laboratory we both h...

Calcium and transmitter release.

The mechanism of transmitter release by intracellular Ca has been explored by recording presynaptic Ca concentration ([Ca2+]i) with Ca-sensitive fluorescent dyes and by controlling [Ca2+]i with photosensitive Ca chelators. [Ca2+]i decays slowly (in seconds) after presynaptic action potentials, while transmitter release lasts only a few ms after each spike at fast synapses. Simulations of Ca dif...

The Nanophysiology of Fast Transmitter Release

Action potentials invading the presynaptic terminal trigger discharge of docked synaptic vesicles (SVs) by opening voltage-dependent calcium channels (CaVs) and admitting calcium ions (Ca(2+)), which diffuse to, and activate, SV sensors. At most synapses, SV sensors and CaVs are sufficiently close that release is gated by individual CaV Ca(2+) nanodomains centered on the channel mouth. Other sy...