![Page 1: COGNITIVE SCIENCE 17 The Chemical Brainpineda/COGS17/Overheads... · 2010. 1. 29. · Receptor Action Ionotropic (ligand gated receptor) Opens ion channel in receptor itself Ions](https://reader036.vdocument.in/reader036/viewer/2022071509/6129dd7371982e3d571b7907/html5/thumbnails/1.jpg)
COGNITIVE SCIENCE 17
The Chemical Brain
Part 1
Matt Schalles, Rev.
![Page 2: COGNITIVE SCIENCE 17 The Chemical Brainpineda/COGS17/Overheads... · 2010. 1. 29. · Receptor Action Ionotropic (ligand gated receptor) Opens ion channel in receptor itself Ions](https://reader036.vdocument.in/reader036/viewer/2022071509/6129dd7371982e3d571b7907/html5/thumbnails/2.jpg)
Neurotransmitters I
![Page 3: COGNITIVE SCIENCE 17 The Chemical Brainpineda/COGS17/Overheads... · 2010. 1. 29. · Receptor Action Ionotropic (ligand gated receptor) Opens ion channel in receptor itself Ions](https://reader036.vdocument.in/reader036/viewer/2022071509/6129dd7371982e3d571b7907/html5/thumbnails/3.jpg)
Graded Potentials
● Depolarization (EPSP)● Vm becomes more positive ● Na+ flows in, sometimes Ca++● Can lead to opening of voltage gated channels
● Hyperpolarization (IPSP)● Vm becomes more negative ● K+ efflux, or Cl- influx● Prevents opening of VG channels
![Page 4: COGNITIVE SCIENCE 17 The Chemical Brainpineda/COGS17/Overheads... · 2010. 1. 29. · Receptor Action Ionotropic (ligand gated receptor) Opens ion channel in receptor itself Ions](https://reader036.vdocument.in/reader036/viewer/2022071509/6129dd7371982e3d571b7907/html5/thumbnails/4.jpg)
3 Types of Ion Channels● Channels that transduce
● Ligand Gated (same as ionotropic receptors)– Found in dendrites, cell body, and axon terminal
● Mechanically Gated– Commonly found in sensory neurons
● Channels that propagate● Voltage Gated
– Found all throughout neuron membrane– Propagate post synaptic potentials and action potentials
![Page 5: COGNITIVE SCIENCE 17 The Chemical Brainpineda/COGS17/Overheads... · 2010. 1. 29. · Receptor Action Ionotropic (ligand gated receptor) Opens ion channel in receptor itself Ions](https://reader036.vdocument.in/reader036/viewer/2022071509/6129dd7371982e3d571b7907/html5/thumbnails/5.jpg)
Receptor Action
● Ionotropic (ligand gated receptor)● Opens ion channel in receptor itself● Ions produce either excitation or inhibition● Fast action
● Metabotropic (g-protein coupled receptor)● Sets off cascade of chemical events● Can lead to ion channel opening on another
protein● Can lead to other, long-term changes● Slower action
![Page 6: COGNITIVE SCIENCE 17 The Chemical Brainpineda/COGS17/Overheads... · 2010. 1. 29. · Receptor Action Ionotropic (ligand gated receptor) Opens ion channel in receptor itself Ions](https://reader036.vdocument.in/reader036/viewer/2022071509/6129dd7371982e3d571b7907/html5/thumbnails/6.jpg)
![Page 7: COGNITIVE SCIENCE 17 The Chemical Brainpineda/COGS17/Overheads... · 2010. 1. 29. · Receptor Action Ionotropic (ligand gated receptor) Opens ion channel in receptor itself Ions](https://reader036.vdocument.in/reader036/viewer/2022071509/6129dd7371982e3d571b7907/html5/thumbnails/7.jpg)
![Page 8: COGNITIVE SCIENCE 17 The Chemical Brainpineda/COGS17/Overheads... · 2010. 1. 29. · Receptor Action Ionotropic (ligand gated receptor) Opens ion channel in receptor itself Ions](https://reader036.vdocument.in/reader036/viewer/2022071509/6129dd7371982e3d571b7907/html5/thumbnails/8.jpg)
The Life Cycle of a Conventional NT
● Biosynthesis & Storage● Release● Receptor Action● Inactivation
![Page 9: COGNITIVE SCIENCE 17 The Chemical Brainpineda/COGS17/Overheads... · 2010. 1. 29. · Receptor Action Ionotropic (ligand gated receptor) Opens ion channel in receptor itself Ions](https://reader036.vdocument.in/reader036/viewer/2022071509/6129dd7371982e3d571b7907/html5/thumbnails/9.jpg)
Biosynthesis
Precursor(s) Transmitter
Enzyme(s)
![Page 10: COGNITIVE SCIENCE 17 The Chemical Brainpineda/COGS17/Overheads... · 2010. 1. 29. · Receptor Action Ionotropic (ligand gated receptor) Opens ion channel in receptor itself Ions](https://reader036.vdocument.in/reader036/viewer/2022071509/6129dd7371982e3d571b7907/html5/thumbnails/10.jpg)
Storage
● Synaptic vesicles made by Golgi apparatus in cell body
● Precursors, enzymes, and vesicles are transported from cell body down axon to terminal
● At terminal, NTs are synthesized and packaged into vesicles
● Filled vesicles dock onto proteins in terminal
![Page 11: COGNITIVE SCIENCE 17 The Chemical Brainpineda/COGS17/Overheads... · 2010. 1. 29. · Receptor Action Ionotropic (ligand gated receptor) Opens ion channel in receptor itself Ions](https://reader036.vdocument.in/reader036/viewer/2022071509/6129dd7371982e3d571b7907/html5/thumbnails/11.jpg)
Release
● Action potential opens channels for Ca++ to enter terminal membrane
● Vesicles to undock and move to membrane
● Vesicles fuse with membrane and empty transmitter into synapse (exocytosis)
![Page 12: COGNITIVE SCIENCE 17 The Chemical Brainpineda/COGS17/Overheads... · 2010. 1. 29. · Receptor Action Ionotropic (ligand gated receptor) Opens ion channel in receptor itself Ions](https://reader036.vdocument.in/reader036/viewer/2022071509/6129dd7371982e3d571b7907/html5/thumbnails/12.jpg)
![Page 13: COGNITIVE SCIENCE 17 The Chemical Brainpineda/COGS17/Overheads... · 2010. 1. 29. · Receptor Action Ionotropic (ligand gated receptor) Opens ion channel in receptor itself Ions](https://reader036.vdocument.in/reader036/viewer/2022071509/6129dd7371982e3d571b7907/html5/thumbnails/13.jpg)
![Page 14: COGNITIVE SCIENCE 17 The Chemical Brainpineda/COGS17/Overheads... · 2010. 1. 29. · Receptor Action Ionotropic (ligand gated receptor) Opens ion channel in receptor itself Ions](https://reader036.vdocument.in/reader036/viewer/2022071509/6129dd7371982e3d571b7907/html5/thumbnails/14.jpg)
Inactivation
Breakdown Products
Transmitter
Enz
yme(
s)
• Destruction • Reuptake• Diffusion
![Page 15: COGNITIVE SCIENCE 17 The Chemical Brainpineda/COGS17/Overheads... · 2010. 1. 29. · Receptor Action Ionotropic (ligand gated receptor) Opens ion channel in receptor itself Ions](https://reader036.vdocument.in/reader036/viewer/2022071509/6129dd7371982e3d571b7907/html5/thumbnails/15.jpg)
Axon Terminal Activity Regulation● Autoreceptors● Heteroreceptors● Retrograde Signals
![Page 16: COGNITIVE SCIENCE 17 The Chemical Brainpineda/COGS17/Overheads... · 2010. 1. 29. · Receptor Action Ionotropic (ligand gated receptor) Opens ion channel in receptor itself Ions](https://reader036.vdocument.in/reader036/viewer/2022071509/6129dd7371982e3d571b7907/html5/thumbnails/16.jpg)
PresynapticAutoreceptor=
![Page 17: COGNITIVE SCIENCE 17 The Chemical Brainpineda/COGS17/Overheads... · 2010. 1. 29. · Receptor Action Ionotropic (ligand gated receptor) Opens ion channel in receptor itself Ions](https://reader036.vdocument.in/reader036/viewer/2022071509/6129dd7371982e3d571b7907/html5/thumbnails/17.jpg)
PresynapticHeteroreceptors
![Page 18: COGNITIVE SCIENCE 17 The Chemical Brainpineda/COGS17/Overheads... · 2010. 1. 29. · Receptor Action Ionotropic (ligand gated receptor) Opens ion channel in receptor itself Ions](https://reader036.vdocument.in/reader036/viewer/2022071509/6129dd7371982e3d571b7907/html5/thumbnails/18.jpg)
Depolarization induced suppression of excitation
![Page 19: COGNITIVE SCIENCE 17 The Chemical Brainpineda/COGS17/Overheads... · 2010. 1. 29. · Receptor Action Ionotropic (ligand gated receptor) Opens ion channel in receptor itself Ions](https://reader036.vdocument.in/reader036/viewer/2022071509/6129dd7371982e3d571b7907/html5/thumbnails/19.jpg)
How do we know what we know?Loss of function
– Head trauma– electrical/chemical
lesion– Magnetic pulses– Genetic knockouts
Gain of function– Genetic knock-in– Magnetic/electrical
pulses– chemicals
● Tools for Observation● Tools for manipulation
![Page 20: COGNITIVE SCIENCE 17 The Chemical Brainpineda/COGS17/Overheads... · 2010. 1. 29. · Receptor Action Ionotropic (ligand gated receptor) Opens ion channel in receptor itself Ions](https://reader036.vdocument.in/reader036/viewer/2022071509/6129dd7371982e3d571b7907/html5/thumbnails/20.jpg)
Principles of Psychopharmacology● Psychotropics – drugs affecting perception,
mood, & behavior● Pharmacokinetics – absorption, distribution,
breakdown, & excretion of drugs● Pharmacodynamics – effect drug exerts
![Page 21: COGNITIVE SCIENCE 17 The Chemical Brainpineda/COGS17/Overheads... · 2010. 1. 29. · Receptor Action Ionotropic (ligand gated receptor) Opens ion channel in receptor itself Ions](https://reader036.vdocument.in/reader036/viewer/2022071509/6129dd7371982e3d571b7907/html5/thumbnails/21.jpg)
Pharmacokinetics – Absorption● Types of Administration
– Injection– Oral– Topical
● Measurements of drug concentration
– Blood plasma– microdialysis
![Page 22: COGNITIVE SCIENCE 17 The Chemical Brainpineda/COGS17/Overheads... · 2010. 1. 29. · Receptor Action Ionotropic (ligand gated receptor) Opens ion channel in receptor itself Ions](https://reader036.vdocument.in/reader036/viewer/2022071509/6129dd7371982e3d571b7907/html5/thumbnails/22.jpg)
Pharmacokinetics - Distribution● Properties affecting absorption
– ph – Lipid vs water solubility
● Impediments to drugs– Inactivating enzymes
● MAO in gut– Depot binding
● Blood albumin● Fat cells
● Blood Brain Barrier– Faster drugs get past this, the 'better' the high
![Page 23: COGNITIVE SCIENCE 17 The Chemical Brainpineda/COGS17/Overheads... · 2010. 1. 29. · Receptor Action Ionotropic (ligand gated receptor) Opens ion channel in receptor itself Ions](https://reader036.vdocument.in/reader036/viewer/2022071509/6129dd7371982e3d571b7907/html5/thumbnails/23.jpg)
How much is too much?
Therapeutic Index = ratio of Lethal Dose to Effective Dose
– High therapeutic index = relatively safe drug– Low means proceed w/ caution
![Page 24: COGNITIVE SCIENCE 17 The Chemical Brainpineda/COGS17/Overheads... · 2010. 1. 29. · Receptor Action Ionotropic (ligand gated receptor) Opens ion channel in receptor itself Ions](https://reader036.vdocument.in/reader036/viewer/2022071509/6129dd7371982e3d571b7907/html5/thumbnails/24.jpg)