Psychology 101: Introductory Psychology
Professor Geoffrey T. Fong

Some Important Neurotransmitters

1. Acetylcholine
   1. Excitatory neurotransmitter (makes it more likely that the receiving neuron will initiate an action potential)

   2. Found in skeletal muscles; very common

   3. Also found in the brain
      • Alzheimer's disease may be associated with the death of cholinergic neurons in the brain (suffix "-ergic": a neuron that has receptors for that neurotransmitter; thus, "cholinergic neurons" are neurons that have receptors for (acetyl)choline)

2. Dopamine
   1. Inhibitory neurotransmitter (makes it less likely that the receiving neuron will initiate an action potential)

   2. Very interesting because it is implicated in a number of disorders:
      • Parkinson's disease--due to destruction of the dopaminergic neurons in the substantia nigra (part of the limbic system that is associated with movement)

      • Schizophrenia--may be due (in part) to overactivity of dopaminergic neurons.

3. Glutamate (Glutamic acid)
   1. Excitatory neurotransmitter

   2. Found in very simple organisms

   3. Chinese Food syndrome--MSG

4. GABA (Gamma-aminobutyric acid)
   1. Inhibitory neurotransmitter

   2. Implicated in Huntington's disease: perhaps due to loss of GABA-ergic neurons in motor areas

5. Serotonin
   1. Inhibitory neurotransmitter

   2. Involved in depression (Prozac and other selective serotonin reuptake inhibitors, or SSRI, help alleviate depression by making more serotonin available in the synapse)