1. Read page 424-425 on drugs and the brain What 3 major concepts should we study to understand this article further?

2. Synapse sin-aps, si-naps Synapse (noun) Small gap between nerve cells (noun) Small gap between nerve cells Use in a sentence: A synapse is cool.

3. Neurotransmitters and The Synapse

4.  Synapse: unique junction that mediates information flow from one neuron to another or effector cell… huh?

6.  Most synapses occur between axon of one nerve and the dendrite of another… BUT

7. Pre vs Post Presynaptic neuron- carries impulse towards a synapse “Sender” Postsynaptic neuron- carries impulse away from a synapse “receiver”

9.  TWO TYPES:  A. electrical synapse  B. chemical synapse

10. Electrical Synapse  Allow current carrying ions to flow directly from one neuron to the next  Found in the brain, limited in adulthood  Most are replaced by chemical synapses

11. Chemical Synapses  -release/reception of neurotransmitters  Neurotransmitters act to open/close ion channels

12. Anatomy of the chemical synapse  axonal terminal synaptic vesicles synaptic vesicles receptor region receptor region synaptic cleft synaptic cleft

13. Information Transfer Across Chemical Synapses  1. Calcium gates open in the presynaptic axonal terminal  Depolarization causes voltage-gated Ca2+ channels to open

14.  2. Neurotransmitter is released Direct result of calcium being present Exocytosis

15.  3. Neurotransmitter binds to post-synaptic receptors  4. Ion channels open in the post-synaptic membrane Boom!

16. Neurotransmitters -language of the nervous system -50 known NT

17. Classification 1. Acetylcholine (ACh) -first identified, best understood 2. Biogenic Amines Include: dopamine, norepinephrine and epinephrine, histamine and serotonin

18. 3. Amino Acids 4. Peptides (neuropeptides) substance P, endorphins, 5. Novel Messengers ATP Nitric Oxide Carbon Monoxide

19. Synthesis of Neurotransmitters