PCOL Tables

• Voltage-gated Channels

  • Sodium Channels
  • Potassium Channels
  • Calcium Channels
• Under Sodium Channels

  • Tetrodotoxin (TTX) - Blocks the channel from outside - Pufferfish
  • Batrachotoxin (BTX) - Slows inactivation, shifts activation - Colombian Frog
• Under Potassium Channel

  • Apamin - Blocks SMALL Ca-activated Potassium channel - Honeybee
  • Charybdotoxin - Blocks BIG Ca-activated Potassium channel - Scorpion
• Under Calcium Channel

  • Omega conotoxin - Blocks N-type channel - Pacific Cone Snail
  • Agatoxin - Blocks P-type channel - Funnel web spider
• Ligand-gated Channels

  • Nicotinic Acetylcholine Receptors
  • GABA A Receptors
  • Glycine Receptors
  • AMPA Receptors
• Under Nicotinic Acetylcholine Receptor

  • a-Bungarotoxin - Irreversible antagonist - Marine snake
• Under GABA A Receptor

  • Picrotoxin - Blocks channel - South Pacific Plant
• Under Glycine Receptor

  • Strychnine - Competitive antagonist - Indian Plant
• Under AMPA Receptor

  • Philanthotoxin - Blocks channel - Wasp
• Acetylcholine


  Cell bodies at all levels; long and short connections
• Muscarinic (M1)


  Muscarine, Excitatory: ↓ in K+ conductance; ↑ IP3, DAG
• Muscarinic (M2)


  Muscarine, bethanechol, Inhibitory: ↑ K+ conductance; ↓ cAMP
• Nicotinic


  Nicotine, Excitatory: ↑ cation conductance
• Dopamine


  Cell bodies at all levels; short, medium, and long connections
• D1


  Dihydrexidine, Inhibitory (?): ↑ cAMP
• D2


  Bromocriptine, Inhibitory (presynaptic): ↓ Ca2+; Inhibitory (postsynaptic): ↑ in K+ conductance, ↓ cAMP
• GABA


  Supraspinal and spinal interneurons involved in pre- and postsynaptic inhibition
• GABAA


  Muscimol, Inhibitory: ↑ Cl– conductance
• GABAB


  Baclofen, Inhibitory (presynaptic): ↓ Ca2+ conductance; Inhibitory (postsynaptic): ↑ K+ conductance
• Glutamate


  Relay neurons at all levels and some interneurons
• 1. Methyl-D-aspartate (NMDA)


  NMDA, Excitatory: ↑ cation conductance, particularly Ca2+
• AMPA


  AMPA, Excitatory: ↑ cation conductance
• Kainate


  Kainic acid, domoic acid, Excitatory: ↑ cation conductance
• Metabotropic


  ACPD, quisqualate, Inhibitory (presynaptic): ↓ Ca2+ conductance, ↓ cAMP; Excitatory: ↓ K+ conductance, ↑ IP3, DAG
• Glycine


  Spinal interneurons and some brain stem interneurons, Inhibitory: ↑ Cl– conductance
• 5-Hydroxytryptamine (serotonin)

  Cell bodies in mid-brain and pons project to all levels
• HT1A


  Eptapirone, Inhibitory: ↑ K+ conductance, ↓ cAMP
• HT2A


  LSD, Excitatory: ↓ K+ conductance, ↑ IP3, DAG
• HT3

  methyl-5-HT, Excitatory: ↑ cation conductance
• 1. HT4


  Cisapride, Excitatory: ↓ K+ conductance
• Norepinephrine


  Cell bodies in pons and brain stem project to all levels
• α1


  Phenylephrine, Excitatory: ↓ K+ conductance, ↑ IP3, DAG
• α2


  Clonidine, Inhibitory (presynaptic): ↓ Ca2+ conductance; Inhibitory: ↑ K+ conductance, ↓ cAMP
• β1


  Isoproterenol, dobutamine, Excitatory: ↓ K+ conductance, ↑ cAMP
• β2


  Albuterol, Inhibitory: may involve ↑ in electrogenic sodium pump; ↑ cAMP
• Histamine


  Cells in ventral posterior hypothalamus
• H1


  2(m-fluorophenyl)-histamine, Excitatory: ↓ K+ conductance, ↑ IP3, DAG
• H2


  Dimaprit, Excitatory: ↓ K+ conductance, ↑ cAMP
• H3


  1. α-methyl-histamine, Inhibitory autoreceptors
• Opioid peptides


  Cell bodies at all levels; long and short connections