The Axon and the Neurotransmitter

1. The Axon and the Neurotransmitter A story of electrical and chemical transmission Put pg 26 & 27 on board

2. The Neuron

3. The cell is the creative space • The NT (neurotransmitter) is formed in the cell (draw pg 12) • A gene (Pre-propeptide) in the cell is transformed into Primary RNA which is transformed into Alternate RNAs which enter the reticulum where an enzyme clips off it’s tail (the pre). It enters the vesticle (a small sack) where it is converted into the Neuropeptide NT (or just NT) and is then taken down the axon

4. The enzyme is also formed in the cell • The DNA is the template for RNA which is the template for the protein molecules that form the enzymes • These enzymes also travel down the axon

5. Where do you suppose receptors are formed? • Yep! In the cell. Receptors, like enzymes, are also protein molecules that are formed in the cell and travel to the axon

6. Messages • Basically, messages come in thru the dendrites and leave thru the Axon Terminals • When traveling down the axon the NTs are traveling electrically thru conduction • When they reach the end of the Axon they are still in the vesticle, which protects them from the enzymes • They then are released into the synapse and move thru a chemical process called transmission

7. Chemical Transmission(drawing of synapse pg 26) • In the pre-synaptic Axon Terminal the NT arrives in it’s vesticle. Along side are Mitochondria which provide energy for the process. • The vesticle releases the NT into the Synapse and one of four things may occur • It may travel to a receptor on the post synaptic dendrite • It may be destroyed by enzymes • It may be taken back into the Axon Terminal thru the Re-Uptake pump and resealed in vesticles for future use • It may escape and affect other distal receptors

8. Basics of how psychotropics work • Psychotropics may destroy enzymes • Psychotropics may block the reuptake pump • Psychotropics cause more receptors to be made (upregulation) • or less to be made (downregulation)

9. What happens to the NT if it gets across to the next neuron? • If a NT attaches to the receptor, a G-Protein and an enzyme will produce a “second messenger” • Another enzyme will break down the second messenger and form transcription factors • Transcription Factors then activate the DNA gene and…… The process starts all over again

10. http://www.psychiatrist.com/pcc/brainstorm/br6010.htm

11. Transcription Factors http://www.psychiatrist.com/pcc/brainstorm/br6010.htm (Stephen Stahl)

12. What if the NT enters the Reuptake Process?

13. Sometimes the NT escapes • Allosteric Modulation- This is when two different receptors using different NTs are arranged so that they effect a single receptor • We will discuss this later, but basically the escapee NT acts indirectly to modify the action of another receptor.

14. This is not a Static Process Receptors live 12-24 hours and then are reabsorbed into the cell Depending on the type of NT and type of receptor, activity can occur instantaniously or beyond a 10 day process (draw table pg 26) We know that Psychotropics take time to work…why do you think this is?

15. Why do you need to know all of these specifics? • Mainly because science is an ever evolving process. What we first believed about how psychotropics work has changed. The processes, which used to be thought to be related to lacking neurons or lacking receptors, now encompasses gene expression, second messengers, and even receptors distant from the transmission site. • The better understanding you have, the better you can understand the medications your clients are using.