A neuron that releases a neurotransmitter.
A neuron receiving a neurotransmitter.
The process of impulse movement along an axon.
The passage of an impulse across a synaptic space.
A brief change in a neural cell's electrical potential from its resting state. This occurs through the activation of excitatory receptors on the dendrites or cell body.
The space between nerve cells.
Messenger molecules secreted by neurons which then may influence the functioning of adjacent neurons; manufactured in the cell body and transported down the action for storage in vesicles. AKA - neuromodulators
Short, branched structures projecting out from the cell body that receive and conduct information to the cell body.
A long neural cell fiber that serves to conduct impulses away from the cell body.
Extremely fine projections on dendrites; common locations for synapses.
Enlarged structures at the end of an axon.
2 Common Properties of Neurotransmitters
1) They are found within neurons and released as a result of a nerve impulse.
2)Produce as physiologic effect on a neuron
A neurotransmitter classification that is comprised of epinephrine, norepinephrine, dopamine, serotonin, histamine, and acetylcholine.
A neurotransmitter classification that is comprised of endorphins, enkephalins, corticotropin releasing factor, and substance P. These substances have purported effects on physiological systems such as pain response, memory/learning, appetite, and temperature control.
Amino Acid Neurotransmission
A neurotransmitter classification that is comprised of amino acids such as glutamate, aspartate, Gamma aminobutyric acid (GABA), and glycine.
Mirror-image amino acids.
Support cells surrounding neurons.
2 Functional Effects of Neurotransmitters on Neurons
1) Excitatory - to activate an adjacent neuron
2) Inhibitory - reduce nerve cell excitability
Reuptake transporter pump
A protein structure in the cell membrane that allow neurotransmitters to reenter the nerve cell and be repackaged into vesicles for use at a later time. (Many of the antidepressants operate via reuptake inhibition.)
Protein molecules produced in the neuron and embedded in the cell membrane. They contain binding sites for messenger molecules attach themselves, and activate the receptor. They have a life span of 12 - 24 hours.
2 Functional Categories of Neuron Receptors
Types of signaling mechanisms
1)Ion Channel Mediated Process
2) G-protein mediated second messenger system
Tiny pores (receptors) on the surface of nerve cell membranes.
When ligands bind to these ion channels the channel opens transiently and allows ions to pass throughout the membrane. Responsible for rapid and transient changes in nerve cell activity.
Electrically charged molecules.
Actions that occur when ligands bind to receptors that activate second messenger systems. Responsible for gradual changes in neuronal functioning that may take place over hours, weeks, or even months.
Common neuronal malfunctions that underlie mental illness
1)Production of neurotransmitters may be inhibited, thus little neurotransmitter is available for release.
2)Neurotransmitters are subject to excessive enzyme degradation
3)Biological/drug based disorders that facilitate or inhibit the release of nuerotransmitters
4)Process of reuptake absorption may be altered.
5)Abnormal up/down regulation of recptors.
6)Pthological alterations in gene expression.
Tiny protein molecules that lie adjacent to the interior surface of a cell's membrane that act like molecular switches activating enzymes in the cytoplasm.
A collection of enzymes that characteristically are water-soluble molecules found in the cytoplasm. Primarily activated by protein phosphorylation. They regulate enzymes protein kinases, which transfer phosphate groups from ATP onto specific protein substrates.