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Related to presynaptic: presynaptic membrane


Situated in front of or occurring before a synapse: a presynaptic nerve fiber; a presynaptic stimulus.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


1. (Physiology) situated near to a nerve synapse
2. (Microbiology) (during meiosis) occurring before the pairing of chromosomes
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014


(ˌpri sɪˈnæp tɪk)

being or occurring on the transmitting end of a discharge across a synapse.
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.
References in periodicals archive ?
Discovered and developed by Sunovion, dasotraline is a new chemical entity that inhibits presynaptic reuptake of dopamine and norepinephrine in the central nervous system.
In addition, the effect to the synapse formation and function were evaluated by setting the numerous spinal densities on dendrite of brain cortex (number of spines per 10 micrometer of dendrites) and mitochondrial function (mitochondrial oxygen efficiency) of hippocampal synaptosomes (isolated presynaptic terminal) as an index.
Synapsins and syntaxins are vesicle proteins that exhibit principal roles in exocytosis and in presynaptic terminals in the clinical symptoms of experimental autoimmune encephalomyelitis (11).
For synaptic maturity, we selected the synaptic profiles contained with the presynaptic area, clustered synaptic vesicles, and postsynaptic area and imaged under 80,000X magnification for analysis (50 synapses for each group).
Blockade of postsynaptic muscarinic receptors reduces the effects of acetylcholine, whereas blockade of presynaptic muscarinic autoreceptors causes an increase in acetylcholine release (4).
Pre-clinical studies have shown that chronic treatment with Bryostatin-1 rescues young Fragile X mice from the disorder phenotypes, including normalization of most Fragile X abnormalities in: 1) hippocampal brain-derived neurotrophic factor expression; 2) postsynaptic density-95 levels; 3) transformation of immature dendritic spines to mature synapses; 4) densities of the presynaptic and postsynaptic membranes, and; 5) spatial learning and memory.
The muscle facilitation apparently resulted from enhanced presynaptic neurotransmitter release since electrophysiological measurements indicated an increase in the miniature end plate potentials (MEPPs) frequency (Rostelato-Ferreira et al., 2014).
When operating as expected, a precise time interval between the post and presynaptic spikes will determine the magnitude of the long-term potentiation or long-term depression of the synapse [3,9].
TCAs act by blocking presynaptic reuptake of norepinephrine or serotonin; they theoretically increase the effects of direct- or indirect-acting agonists at these synapses.[4] TCAs may also block alpha-adrenergic receptors, which causes hypotension resulting from reduction of myocardial contractility and systemic vascular resistance.[4],[5] TCAs inhibit Na/K-ATPase and act like quinidine-like antiarrhythmics by stabilizing excitable membranes and delaying His bundle conduction.
When an action potential (AP) arrives at the presynaptic terminal, calcium (Ca) influx through voltage-gated Ca channels triggers synaptic vesicle fusion and the release of transmitters stored in the synaptic vesicles.
Before 90s presynaptic mechanisms, namely all processes determining the striatal dopamine levels like production, storage, release and reuptake by the dopaminergic terminals, were more commonly accused for LID, as nigral dopaminergic cell loss is the initial and the most prominent pathological finding in PD.