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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.


1. (Physiology) situated near to a nerve synapse
2. (Microbiology) (during meiosis) occurring before the pairing of chromosomes


(ˌpri sɪˈnæp tɪk)

being or occurring on the transmitting end of a discharge across a synapse.
References in periodicals archive ?
The SNCA gene codes for making the alpha-synuclein protein, which is found within neurons at presynaptic nerves and in other cell types.
Our work not only has the capacity to uncover novel aspects in the regulation of presynaptic autophagy and function, but it will also reveal mechanisms of synaptic dysfunction in models of neuronal demise and open new research lines on mechanisms of synaptic plasticity.
Conclusion: These results indicate that TEN enhances the basic synaptic transmission via stimulating presynaptic intracellular calcium.
If you don't have a reservoir of neurotransmitters, the drugs soon may become ineffective or tachyphylactic and cause a greater excretion of neurotransmitters via monoamine oxidase and catechol-O-methyltransferase, creating a deficiency of neurotransmitters in the presynaptic neuron.
In one experiment, directly overexpressing Dscam led to flies with neuron endings (called presynaptic terminals) more than 50 percent longer than normal.
Injectable (ioflupane [123I] injection) "DaTSCAN") is a brain imaging agent to be used in evaluating the distribution of presynaptic dopamine transporters in the striatal region of the brain for diagnosing Parkinson's Syndrome and dementia with Lewy bodies.
Eicosapentaenoic acid (EPA) increases serotonin release from presynaptic neurons by reducing inflammatory signaling molecules in the brain known as E2 series prostaglandins, which inhibit serotonin release and suggests how inflammation may negatively impact serotonin in the brain.
The neurotoxin binds to the presynaptic nerve endings of cholinergic neurons, resulting in a marked reduction in bladder contractions.
On the other hand, another implication could be considered for these reports which is that baclofen affects two presynaptic and postsynaptic types of receptors and the obtained responses are the result of activities of these presynaptic and postsynaptic receptors.
In the study, poor working memory in young and aged rhesus monkeys was associated with a higher incidence of malformed donut-shaped mitochondria in presynaptic terminals.
They found that excess levels of alpha-synuclein accumulated in the presynaptic terminal--part of the junction where axons and dendrites of brain cells meet to exchange chemical signals.