• Neurotransmitters
• Quiz 2 on Friday.
• Review Exam 1 on Friday.

• Na+
• K+
• Ca++
• Cl-

• Na+
• K+
• Ca++
• Cl-

• Ionotropic
• Metabotropic
• Ligand-gated

• Ionotropic
• Metabotropic
• Ligand-gated

• Primary excitatory NT in CNS
• Role in learning (via NMDA receptor)
• Transporters on neurons and glia (astrocytes and oligodendrocytes)
• Linked to umami (savory) taste sensation, think monosodium glutamate (MSG)
• Dysregulation in schizophrenia? (Javitt 2010)

• Primary inhibitory NT in CNS
• Excitatory in developing CNS, [Cl-] in >> [Cl-] out
• Binding sites for benzodiazepines (e.g., Valium), barbiturates, ethanol, etc.

• Primary NT of CNS output
• Somatic nervous system (neuromuscular junction)
• Autonomic nervous system
  • Sympathetic branch: preganglionic neuron
  • Parasympathetic branch: pre/postganglionic
• Inactivation by acetylcholinesterase (AChE)

• aka, nightshade or belladonna

https://en.wikipedia.org/wiki/Mah_Nà_Mah_Nà

Monoamines, do-do do do-do
Monoamines, do do do-do
Monoamines, do do do do-do do do-do do do-do do do do do-do do

Monoamines, do-pa-mine is one
Monoamines, norepi, too
Monoamines, sero-tonin e-pinephrine, dop-a- mine, nor-epinephrine, melatonin, whoo!

Monoamines, mod-u-late neurons
Monoamines, throughout the brain
Monoamines, keep people happy, brains snappy, not sleepy, not sappy, do-do do-do do-do do

• Released by two pathways
  • Substantia nigra -> striatum, meso-striatal projection
  • Ventral tegmental area (VTA) -> nucleus accumbens, ventral striatum, hippocampus, amygdala, cortex; meso-limbo-cortical projection

• Parkinson's Disease (mesostriatal)
  • DA agonists treat (agonists facilitate/increase transmission)
• ADHD (mesolimbocortical)
• Schizophrenia (mesolimbocortical)
  • DA antagonists treat
• Addiction (mesolimbocortical)

• Released by
  • locus coeruleus in pons
  • postganglionic sympathetic neurons onto target tissues
• Role in arousal, mood, eating, sexual behavior

• Monoamine oxidase inactivates monoamines in neurons, astrocytes
• Monoamine oxidase inhibitors (MAOIs) increase NE, DA
  • Inhibiting inactivation ~ -(-1) = + 1
• Treatment for depression, but have side effects

• Released by raphe nuclei in brainstem
• Role in mood, sleep, eating, pain, nausea, cognition, memory
• Modulates release of other NTs
• Most of body's 5-HT regulates digestion

• Seven families (5-HT 1-7) with 14 types
• All but one metabotropic

• Ecstasy (MDMA) disturbs serotonin
• So does LSD
• Fluoxetine (Prozac)
  • Selective Serotonin Reuptake Inhibitor (SSRI)
  • Inhibits reuptake -> increases extracellular concentration
  • Treats depression, panic, eating disorders, others
• 5-HT3 receptor antagonists are anti-mimetics used in treating nausea

• Released by pineal gland into bloodstream

• In brain, released by hypothalamus, projects to whole brain
  • Metabotropic receptors
  • Role in arousal/sleep regulation
• In body, part of immune response

• Gases
  • Nitric Oxide (NO), carbon monoxide (CO)
• Neuropeptides
  • Substance P and endorphins (endogenous morphine-like compounds) have role in pain
  • Orexin/hypocretin, project from lateral hypothalamus across brain, regulate appetite, arousal

• Neuropeptides (continued)
  • Cholecystokinin (CCK) stimulates digestion
  • Oxytocin and vasopressin released by posterior hypothalamus onto posterior pituitary, regulate social behavior

• Gap junctions
• Electrical coupling
• Connect cytoplasm directly
• Fast, but fixed, hard to modulate
• Examples, retina, cardiac muscle

• Specificity: point-to-point vs. broadcast
• Direct vs. modulatory
• Agonists vs. antagonists

• Agonists
  • bind to receptor
  • mimic action of endogenous chemical
• Antagonists
  • bind to receptor
  • block/impede action of endogenous chemical

1. It decreases inhibition
2. It activates a metabotropic Cl- channel
3. It facilitates/increases inhibition
4. It blocks an ionotropic channel

1. It decreases inhibition
2. It activates a metabotropic Cl- channel
3. It facilitates/increases inhibition
4. It blocks an ionotropic channel

• Hormones