VII
Contents
I
Basics and History of Plant Secondary Metabolites
1
Plant Secondary Metabolites and Their General Function in Plants ........... 3
1.1
General Classification of Secondary Metabolites (Details in Part IV) .............................. 4
1.2
Overview of Classes of Secondary Metabolites (Details in Part IV) ................................. 5
1.3
Overview of the Function of Secondary Metabolites in Plants (Details in Part IV) .... 6
1.3.1 Adaptation to a Life on Land ............................................................................................................. 8
1.3.2 Attraction (or Deterrent) of Pollinators and Seed Dispersers ................................................. 8
1.3.3 Defence Against Herbivores, Pathogens and Other Pests ....................................................... 10
1.3.4 Plant-to-Plant Communication ........................................................................................................ 11
1.3.5 Constitutive versus Induced Expression ........................................................................................ 11
1.3.6 Counterstrategies of the Attacker and Use of Plant-Derived Secondary
Metabolites by Other Animals .......................................................................................................... 12
1.3.7 Avoidance of Auto-Toxicity and Premature Toxin Release ....................................................... 13
References ............................................................................................................................................... 16
2
Historical and Current Perspective .................................................................................... 19
2.1
History of Medical Use ....................................................................................................................... 20
2.2
History of Recreational Use ............................................................................................................. 23
References ............................................................................................................................................... 24
II
Drugs and Their Human Receptors
3
GPCRs ..................................................................................................................................................... 29
3.1
G-Protein-Coupled Receptors ......................................................................................................... 30
3.2
Trimeric G-Proteins ............................................................................................................................. 32
3.3
G S , G olf and G i Targeting Adenylyl Cyclase.................................................................................. 35
3.4
G q Targeting Phospholipase C ........................................................................................................ 38
3.5
Signal Termination .............................................................................................................................. 39
References ............................................................................................................................................... 41
4
Ion Channels ...................................................................................................................................... 43
4.1
Channels and Transporters .............................................................................................................. 44
4.2
Membrane Potential and Electrochemical Gradient .............................................................. 46
4.3
Voltage-Gated Ion Channels ........................................................................................................... 47
4.3.1 Voltage-Gated K + -Channels ............................................................................................................... 47
4.3.2 Voltage-Gated Na + -Channels ............................................................................................................ 49
4.3.3 Voltage-Gated Ca 2+ -Channels........................................................................................................... 50
4.3.4 Neuromuscular Junction .................................................................................................................... 51
4.3.5 VOCs and Neurotransmitter Release .............................................................................................. 52
4.4
Extracellular Ligand-Operated Channels: Neurotransmitter Receptors ........................ 53
4.5
TRP Channels ......................................................................................................................................... 54
References ............................................................................................................................................... 56
Contents
I
Basics and History of Plant Secondary Metabolites
1
Plant Secondary Metabolites and Their General Function in Plants ........... 3
1.1
General Classification of Secondary Metabolites (Details in Part IV) .............................. 4
1.2
Overview of Classes of Secondary Metabolites (Details in Part IV) ................................. 5
1.3
Overview of the Function of Secondary Metabolites in Plants (Details in Part IV) .... 6
1.3.1 Adaptation to a Life on Land ............................................................................................................. 8
1.3.2 Attraction (or Deterrent) of Pollinators and Seed Dispersers ................................................. 8
1.3.3 Defence Against Herbivores, Pathogens and Other Pests ....................................................... 10
1.3.4 Plant-to-Plant Communication ........................................................................................................ 11
1.3.5 Constitutive versus Induced Expression ........................................................................................ 11
1.3.6 Counterstrategies of the Attacker and Use of Plant-Derived Secondary
Metabolites by Other Animals .......................................................................................................... 12
1.3.7 Avoidance of Auto-Toxicity and Premature Toxin Release ....................................................... 13
References ............................................................................................................................................... 16
2
Historical and Current Perspective .................................................................................... 19
2.1
History of Medical Use ....................................................................................................................... 20
2.2
History of Recreational Use ............................................................................................................. 23
References ............................................................................................................................................... 24
II
Drugs and Their Human Receptors
3
GPCRs ..................................................................................................................................................... 29
3.1
G-Protein-Coupled Receptors ......................................................................................................... 30
3.2
Trimeric G-Proteins ............................................................................................................................. 32
3.3
G S , G olf and G i Targeting Adenylyl Cyclase.................................................................................. 35
3.4
G q Targeting Phospholipase C ........................................................................................................ 38
3.5
Signal Termination .............................................................................................................................. 39
References ............................................................................................................................................... 41
4
Ion Channels ...................................................................................................................................... 43
4.1
Channels and Transporters .............................................................................................................. 44
4.2
Membrane Potential and Electrochemical Gradient .............................................................. 46
4.3
Voltage-Gated Ion Channels ........................................................................................................... 47
4.3.1 Voltage-Gated K + -Channels ............................................................................................................... 47
4.3.2 Voltage-Gated Na + -Channels ............................................................................................................ 49
4.3.3 Voltage-Gated Ca 2+ -Channels........................................................................................................... 50
4.3.4 Neuromuscular Junction .................................................................................................................... 51
4.3.5 VOCs and Neurotransmitter Release .............................................................................................. 52
4.4
Extracellular Ligand-Operated Channels: Neurotransmitter Receptors ........................ 53
4.5
TRP Channels ......................................................................................................................................... 54
References ............................................................................................................................................... 56