Catecholamines

 

Catecholamine Synthesis, Release, and Inactivation

Tyrosine hydroxylase catalyzes the rate-limiting stepin catecholamine synthesis

Catecholamines are stored in and released from synaptic vesicles

Catecholamine inactivation occurs through the combination of reuptake and metabolism

Organization and Function of the Dopaminergic System

Two important dopaminergic cell groups are found in the midbrain

Ascending dopamine pathways have been implicated in several important behavioral functions

Box 5.1 Clinical Applications Mutations That Affect Dopamine Neurotransmission

There are five main subtypes of dopamine receptors organized into D₁- and D₂-like families

Dopamine receptor agonists and antagonists affect locomotor activity and other behavioral functions

Box 5.2 The Cutting Edge Using Molecular Genetics to Study the Dopaminergic System

Organization and Function of the Noradrenergic System

Norepinephrine is an important transmitter in both the central and peripheral nervous systems

Norepinephrine and epinephrine act through α- and β-adrenergic receptors

The central noradrenergic system plays a significant role in arousal, cognition, and the consolidation of emotional memories

Several medications work by stimulating or inhibiting peripheral adrenergic receptors