1. Neurotransmitters

2. Neurotransmitters videos

3. Neurotransmitters
100+ substances are known or suspected neurotransmitters
Neurotransmitters affect the postsynaptic neurons as long as it remains bound to receptors
Removal is essential for normal synaptic function

4. Neurotransmitters, cont.
NTs may be
EXCITATORY – stimulate the brain
INHIBITORY – calm the brain

5. Neurotransmitters, cont.
Neurotransmitters are removed in four ways
1. NTs diffuse away from synaptic cleft
2. Some NTs are destroyed by enzymes
3. Active transport into the releasing (presynaptic) neuron REUPTAKE
4. Active transport into neighboring neuroglia UPTAKE

6. Acetylcholine (Ach) One of the best studied NTs
Released in both PNS & CNS
Ach may be excitatory at some synapses (like the NMJ)
Ach may also be inhibitory at some synapses
Ach video

7. CNS Neurotransmitters
INHIBITORY:
GABA
Glycine
EXCITATORY:
Glutamate
Aspartate
These four are also amino acids
Some drugs, such as Valium, Ativan, Xanax and other benzodiazepines, increase the action of GABA, for anti-anxiety, sedative, anti-seizure results

8. Modified Amino Acids Norepinephrine (NE) Dopamine
Arousal (waking from sleep), dreaming, regulating mood
Dopamine
Emotional responses, addictive behaviors, and pleasurable experiences
Regulate skeletal muscle tone and some aspects of movement
Schizophrenia is linked to excess dopamine

9. Drugs & NTs
Cocaine produces euphoria by blocking the reuptake of dopamine
Other drugs interact with receptors involved in the endorphine system

10. Parkinson’s Disease Degenerative disorder of the CNS
Mainly affects the motor system
Death of dopamine-generating cells
Early symptoms: shaking, slowness of movement, difficulty walking
Later symptoms: thinking, dementia
Most cases occur after the age of 50
Michael J Fox, Mohammad Ali

11. Seratonin
Sensory perception, temperature regulation, control of mood, appetite, and onset of sleep
Relaxation & sleepiness
SSRIs
Selective Seratonin reuptake inhibitors
Example: Prozac
Block the reuptake of serotonin
Prolongs the activity of serotonin
Provides relief for those suffering from some forms of depression
NT Serotonin is made from tryptophan (turkey) – concentration low in protein rich meal – unlikely to actually make us feel sleepy. However, carb-rich foods result in release of serotonin in brain – making us sleepy & relaxed

12. Endorphins Endorphins are neuropeptides
Neuropeptides are aminoacids linked by peptide bonds
Endorphins are the body’s natural painkillers

13. Frog heart physiology vid