Chapter 4 Channels and Transporters 69 Chapter 6 Neurotransmitters and Their Overview Receptors 129 Ion Channels Underlying Action Potentials 69 Overview 129 Box A The Patch Clamp Method 70 Categories of Neurotransmitters 129 The Diversity of Ion Channels 73 Acetylcholine 129 Box B Expression of lon Channels in Xenopus Box A Addiction 134 Oocytes 75 Box B Neurotoxins that Act on Postsynaptic Voltage-Gated Ion Channels 36 Ligand-Gated Ion Channels 78 Glutamate 137 Stretch- and Heat-Activated Channels 78 Box C Myasthenia Gravis: An Autoimmune The Molecular Structure of Ion Channels 79 Disease of Neuromuscular Synapses 1 Box C Toxins That Poison lon Channels GABA and Glycine 143 Box D Diseases Caused by Altered lon Box D Excitotoxicity Following Acute Brain Channels 84 Injury 145 Active Transporters Create and Maintain Ion The Biogenic Amines 14 Gradients 86 Functional Properties of the Na*/K+ Pump 87 Box E Biogenic Amine Neurotransmitters and The Molecular Structure of the Na/K Pump 89 Psychiatric Disorders 148 Summary 90 ATP and Other Purines 152 Peptide Neurotransmitters 153 Chapter 5 Synaptic Transmission 93 Unconventional Neurotransmitters 157 Overview 93 Box F Marijuana and the Brain 160 Electrical Synapses Summary 161 Signal Transmission at Chemical Synapses 96 Properties of Neurotransmitters 96 Chapter 7 Molecular Signaling within Box A Criteria that define a Neurons 165 Neurotransmitter 99 Overview 165 Quantal Release of Neurotransmitters 102 Strategies of Molecular Signaling 16 Release of Transmitters from Synaptic Vesicles 103 The Activation of Signaling Pathways 167 Local Recycling of Synaptic Vesicles 105 Receptor Types 16 The Role of Calcium in Transmitter Secretion 107 G-Proteins and Their Molecular Targets 170 Box B Diseases That Affect the Presynaptic Second Messengers 172 Terminal 108 Second Messenger Targets: Protein Kinases and Molecular Mechanisms of Transmitter Secretion 110 Phosphatases 175 Neurotransmitter Receptors 113 Nuclear Signaling 178 Box C Toxins that Affect transmitter Release 115 Examples of Neuronal Signal Transduction 181 Summary 184 Postsynaptic Membrane Permeability Changes during Synaptic Transmission 116 Excitatory and Inhibitory Postsynaptic Potentials 121 Summation of Synaptic Potentials 123 Two Families of Postsynaptic ReceptorsChapter 4 Channels and Transporters 69 Overview 69 Ion Channels Underlying Action Potentials 69 BOX A The Patch Clamp Method 70 The Diversity of Ion Channels 73 BOX B Expression of Ion Channels in Xenopus Oocytes 75 Voltage-Gated Ion Channels 76 Ligand-Gated Ion Channels 78 Stretch- and Heat-Activated Channels 78 The Molecular Structure of Ion Channels 79 BOX C Toxins That Poison Ion Channels 82 BOX D Diseases Caused by Altered Ion Channels 84 Active Transporters Create and Maintain Ion Gradients 86 Functional Properties of the Na+/K+ Pump 87 The Molecular Structure of the Na+/K+ Pump 89 Summary 90 Chapter 5 Synaptic Transmission 93 Overview 93 Electrical Synapses 93 Signal Transmission at Chemical Synapses 96 Properties of Neurotransmitters 96 BOX A Criteria That Define a Neurotransmitter 99 Quantal Release of Neurotransmitters 102 Release of Transmitters from Synaptic Vesicles 103 Local Recycling of Synaptic Vesicles 105 The Role of Calcium in Transmitter Secretion 107 BOX B Diseases That Affect the Presynaptic Terminal 108 Molecular Mechanisms of Transmitter Secretion 110 Neurotransmitter Receptors 113 BOX C Toxins That Affect Transmitter Release 115 Postsynaptic Membrane Permeability Changes during Synaptic Transmission 116 Excitatory and Inhibitory Postsynaptic Potentials 121 Summation of Synaptic Potentials 123 Two Families of Postsynaptic Receptors 124 Summary 126 Chapter 6 Neurotransmitters and Their Receptors 129 Overview 129 Categories of Neurotransmitters 129 Acetylcholine 129 BOX A Addiction 134 BOX B Neurotoxins that Act on Postsynaptic Receptors 136 Glutamate 137 BOX C Myasthenia Gravis: An Autoimmune Disease of Neuromuscular Synapses 140 GABA and Glycine 143 BOX D Excitotoxicity Following Acute Brain Injury 145 The Biogenic Amines 147 BOX E Biogenic Amine Neurotransmitters and Psychiatric Disorders 148 ATP and Other Purines 152 Peptide Neurotransmitters 153 Unconventional Neurotransmitters 157 BOX F Marijuana and the Brain 160 Summary 161 Chapter 7 Molecular Signaling within Neurons 165 Overview 165 Strategies of Molecular Signaling 165 The Activation of Signaling Pathways 167 Receptor Types 168 G-Proteins and Their Molecular Targets 170 Second Messengers 172 Second Messenger Targets: Protein Kinases and Phosphatases 175 Nuclear Signaling 178 Examples of Neuronal Signal Transduction 181 Summary 184 Contents ix Purves3/eFM 5/13/04 12:59 PM Page ix