Monoaminergic Systems

Central monoaminergic systems are involved in behavioral arousal, attention, motivation, and control of motor, nociceptive, and autonomic processing. They include dopaminergic, noradrenergic, serotonergic, and histaminergic neurons with cell bodies in restricted areas of the brainstem and hypothalamus and widespread axonal projections targeting multiple brain regions. Via their multiple receptor mechanisms, these systems exert a complex and behavioral-state-dependent modulation of excitability of neurons and neuronal networks. In the periphery, norepinephrine is the major neurotransmitter of the sympathetic system. Monoaminergic systems are affected in genetic disorders of monoamine metabolism, neurodegenerative conditions, and psychiatric disorders. These systems are also a major target for pharmacologic therapy.