Psych C61

Where does acetylcholine come from?

Week 5 Notes

Neurotransmitters:

● Acetylcholine (ACh)

○ Found in-

■ Parasympathetic nervous system

■ Neuromuscular junction (NMJ)

■ Brain

○ Produced by-

■ Basal forebrain nuclei

■ Midbrain pontine nuclei

● Serotonin

○ Produced by-

■ Raphe nucleus

● Dopamine

○ Produced by-

■ Ventral tegmentum

■ Substantia nigra

● Norephrine

○ Produced by-

■ Locus coeruleus

- All of these neurotransmitters are produced by isolated clusters of neurons that are then released to extensive parts of the body

What is the role of norepinephrine?

- Glutamate and GABA are produced everywhere

Blood Brain Barrier (BBB)

● Tiny gaps between blood vessel cell walls

● Blood vessel cells in the brain don’t have these gaps

● In order to cross blood brain barrier there needs to be some sort of mechanism ○ Transport:

■ Glucose sugar, some amino acids

○ Diffusion:

■ Lipophilic and hydrophobic molecules can diffuse through the lipid bilayer cell wall Don't forget about the age old question of How is elimination method used in most formulas?

Toxins:

● Botulinum toxin (Botox)

○ Associated with bacterium clostridium botulinum

○ Taken up into ACh presynaptic terminals

○ Interferes with NT release

○ Reduces effectiveness of ACh at NMJ

○ Can’t infiltrate blood brain barrier

What is botulinum toxin used for?

○ Typical dosage

■ ~100 units

● 1 unit = .05 ng

● 5 billionth of a gram

○ Human LD50

■ ~2ng/kg

■ Death from paralysis of respiration

● Tetrodotoxin (TTX)

○ Found in pufferfish

○ Blocks voltage gated sodium channels

○ Doesn’t cross blood brain barrier

○ Peripheral nerves unable to generate normal action potentials

■ Symptoms:

● Numbness

● Muscle weakness

● Paralysis

○ Death by respiratory paralysis Don't forget about the age old question of How old is the universe according to big bang theory?

● PSP

○ Paralytic shellfish poisoning

○ Saxitoxin

○ Doesn’t cross blood brain barrier

○ Blocks voltage gated sodium channels

● Batrachotoxins

○ Causes voltage gated sodium channels to stay open

- All have different methods of altering the voltage gated sodium channels If you want to learn more check out Can stimulants cause depression?
Don't forget about the age old question of How does an organism defend itself?

People:

● Paracelsus (1493-1541)

○ “Everything is a poison. The difference between a poison and a remedy depends on the dose.” If you want to learn more check out What is the difference between representative heuristic and availability heuristic
If you want to learn more check out What does the nuclear utilization theory state?

Pharmakon

-Means medicine and poison simultaneously