Pathologies Associated with Extracellular Potassium Levels and Synapse Functions

These flashcards cover key vocabulary related to the pathologies associated with extracellular potassium levels and the mechanisms of synaptic transmission.

Extracellular Potassium Levels

Refers to the concentration of potassium ions outside of cells, influencing resting potential and the generation of action potentials.

Resting Potential

The electrical potential across a neuron's membrane when it is not actively sending a signal, typically negative due to ion distribution.

Action Potential (AP)

A rapid rise and fall in membrane potential that occurs when a neuron generates a signal.

Electrical Synapse

A type of synapse that allows direct electrical communication between neurons via gap junctions, with no synaptic cleft.

Chemical Synapse

A type of synapse where neurotransmitters are released from the presynaptic terminal into the synaptic cleft, allowing communication between neurons.

Excitatory Synapse

A synapse where neurotransmitter binding causes depolarization, making the post-synaptic neuron more likely to fire an action potential.

Inhibitory Synapse

A synapse where neurotransmitter binding causes hyperpolarization, making it less likely for the post-synaptic neuron to fire an action potential.

Neurotransmitter

Chemical substances released from neurons to transmit signals across a synapse.

Ligand

A chemical signal, such as a neurotransmitter or hormone, that binds to a receptor to elicit a response in a target cell.

Catecholamines

A group of neurotransmitters, produced by modifying tyrosine including dopamine, norepinephrine, and epinephrine, derived from the amino acid tyrosine, sent by neuron into synapse

Dopamine

A catecholamine located in the basal nuclei of the brain involved in movement control and reward systems, with relevance to conditions like Parkinson's disease.

Norepinephrine and Epinephrine

Neurotransmitters also known as adrenaline, located in the PNS, involved in the autonomic nervous system affecting stress and blood pressure.

Serotonin

A neurotransmitter modified from tryptophan, located in CNS, associated with feelings of well-being and the gut-brain axis.

Endorphins and Enkaphalins

Peptides in the CNS that act as natural pain reducers.

Ligand-gated Ion Channels

Receptors that change their shape upon binding of a ligand, leading to changes in membrane permeability and ion currents.

Synapse

Region of contact between axon terminal and target cell