Norepinephrine Termination of Action Flashcards
What is the PRIMARY mechanism for the termination of action of norepinephrine in the synaptic cleft?
Let’s go to study!!!
The primary mechanism that removes NE from the synaptic cleft is —– into the presynaptic nerve
Reuptake
Up to —–% of the NE released undergoes reuptake into the presynaptic nerve
80%
Most NE is —– and —– into vesicles to be used again
recycled and repackaged
Most NE is recycled and repackaged into vesicles to be used again, however, some NE is metabolized by —– in the nerve terminal
MAO
NE reuptake is blocked by —– and —–.
Tricyclic antidepressants, and
Cocaine
Reuptake can also be accomplished by certain extra-neural tissues. These tissues contain —– and —– to metabolize NE
MAO and COMT
NE may also diffuse away from the synaptic cleft, enter the circulation, and be metabolized in which two organs?
Liver and Kidney
NE may also diffuse away from the synaptic cleft, enter the circulation, and be metabolized in the liver and kidney
by —– and —–.
MAO and COMT
What is the PRIMARY mechanism for the termination of action of norepinephrine in the synaptic cleft?
Reuptake
Approximately —– % of the NE released into the synaptic cleft undergoes reuptake into the presynaptic neuron
80%
Approximately 80% of the NE released into the synaptic cleft undergoes reuptake into the presynaptic neuron. This explains why —— is the primary mechanism of NE’s termination of action.
Reuptake
Most of the NE that doesn’t undergo reuptake diffuses into the ——.
Systemic circulation
Most of the NE that doesn’t undergo reuptake diffuses into the systemic circulation, where it is subject to metabolism by —– and —–.
COMT and MAO
Most of the NE that doesn’t undergo reuptake diffuses into the systemic circulation, where it is subject to metabolism by COMT and MAO in which organs?
liver and kidneys.
