Substance P

Somatostatin

Endorphins and Enkephalins (opioid peptides)

Norepinephrine/Epinephrine

Dopamine

Serotonin

Histamine

Gamma-amino-butyric acid (GABA)

Glycine

Glutamate & Aspartate

Serotonin

Action:

Monoamine

Has inhibitory effect & is a moderator of impulsivity

Has stimulator effect and increased neurotransmission

Major neurotransmitter of parasympathetic NS

Stimulates parasympathetic nerves

Enables storage of recent memory at biochemical level

Norepinephrine/Epinephrine

Action:

Monoamine.

Usually has an excititatory effect

Secreted in brain, spinal cord, hypothalamus, and postganglionic neurons of sympathetic NS

*Degraded by Monoamine Oxidase (MAO) in presynaptic junction

MAO Inhibitors

Function

used to increase monoamines (epi, norepi, sero)

ex. ephedra

GABA

Action:

Plays a role in inhibition

Secreted by nerves of spinal cord, cerebellum, basal ganglia, some parts of cerebral cortex

Glutamic Acid Decarboxylase (GAD) is responsible for synthesizing GABA

Dec. GAD leads to dec. GABA

GABA

Function:

Reduces:

aggression

excitiation

anxiety

Norepinephrine/Epinephrine

Function:

Level in brain effects mood

Stimulates sympathetic (adrenergic) NS for F-or-F

Serotonin

Function:

Regulates:

Mood

Aggression

Excitiation

Anxiety

Dopamine

Action:

Monoamine

Secreted in neurons of substantia nigra

Dopamine

Function:

Regulates fine motor movement

In areas of brain that mediates:

emotions

feelings of pleasure

feelings of pain

awareness

levels of consciousness

ACh

receptor sites

Muscarine receptors

throughout PNS

5-HT1

5-HT2

Norepi/Epi

Receptors

alpha 1

alpha 2

beta 1

beta 2

throughout the CNS

especially RAS (reticular activiating system)

Dopamine

receptors

D2 receptors- pos. psychotic manifestations

(binding of dopamine with D2 stimulates mesolimbic brain pathways and can lead to psychotic manifestations)

D1 receptors - negative manifestations

(decreased motor movement, decreased affect)