• Warm-up
• Neurotransmitters
• Hormones

• Na+
• K+
• Ca++
• Cl-

• Na+
• K+
• Ca++
• Cl-

• Ionotropic
• Metabotropic
• Ligand-gated

• Ionotropic
• Metabotropic
• Ligand-gated

• Glutamate
• GABA
• Acetylcholine
• Dopamine

• Glutamate
• GABA
• Acetylcholine
• Dopamine

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
  • Enteric nervous system

• 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

• It decreases inhibition
• It activates a metabotropic Cl- channel
• It facilitates/increases inhibition
• 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

• Neurocrine
  • Sending cell -> Receiving cell
• Autocrine
  • Sending cell -> itself
  • e.g., presynaptic autoreceptors
• Paracrine
  • Sending cell -> neighboring cells
  • NO and CO NTs

• Endocrine
  • Sending cell -> many cells elsewhere in body
• Pheromone
  • Sending cell -> other animals of same species
• Allomone
  • Sending cell -> cells in other species

• Chemical secreted into blood
• Act on specific target tissues
• Produce specific effects

• Yes, why not?
• No, absolutely not.

• Yes, why not?
• No, absolutely not.

• Melatonin
• Epinephrine/adrenaline
• Oxytocin
• Vasopressin

• Ingestive (eating/ drinking)
  • Fluid levels
  • Na, K, Ca levels
  • Digestion
  • Blood glucose levels

• Reproduction
  • Sexual Maturation
  • Mating
  • Birth
  • Care giving

• Responses to threat/ challenge
  • Metabolism
  • Heart rate, blood pressure
  • Digestion
  • Arousal

• Biological imperatives
• Events are proscribed in space and time
• Foraging/hunting
  • Find targets distributed in space, evaluate, act upon
• Often involve others

• Point to point vs.“broadcast”
  • Wider broadcast than neuromodulators
• Fast vs. slow-acting
• Short-acting vs. long-acting
• Digital (yes-no) vs. analog (graded)
• Voluntary control vs. involuntary

• Chemical messengers stored for later release
• Release follows stimulation
• Action depends on specific receptors
• 2nd messenger systems common

• Wrap-up on hormones
• Quiz 2