HEP (2005) 168:327–365
©cSpringer-Verlag 2005
Effects of Cannabinoids on Neurotransmission
B. Szabo^1 ()·E.Schlicker^2
(^1) Institut für Experimentelle und Klinische Pharmakologie und Toxikologie,
Albert-Ludwigs-Universität, Albertstrasse 25, 79104 Freiburg, Germany
[email protected]
(^2) Institut für Pharmakologie und Toxikologie, Rheinische Friedrich-Wilhelms-Universität,
Reuterstrasse 2b, 53113 Bonn, Germany
1Introduction.................................... 328
2 Effects of Cannabinoids on Ion Channels .................... 328
2.1 EffectsofCannabinoidsonVoltage-GatedIonChannels ............ 329
2.1.1CalciumChannels................................. 329
2.1.2PotassiumChannels................................ 329
2.1.3SodiumChannels ................................. 330
2.2 EffectsofCannabinoidsonLigand-GatedIonChannels ............ 330
2.3 What Is the Functional Consequence of the Inhibition
ofSomadendriticIonChannels? ......................... 330
3 Anatomical Evidence for the Presence of CB 1 Cannabinoid Receptors
in Axon Terminals................................. 331
4 Effects of Cannabinoids on Neurotransmission
in the Central Nervous System .......................... 332
4.1 FastExcitatoryNeurotransmission........................ 332
4.2 FastInhibitoryNeurotransmission........................ 337
4.3 NeurotransmissionviaMonoaminesandAcetylcholine ............ 342
5 Effects of Cannabinoids on Neurotransmission
in the Peripheral Nervous System ........................ 345
6 Mechanism of the Presynaptic Inhibition .................... 349
6.1 InhibitionofCalciumChannels ......................... 349
6.2 ActivationofPotassiumChannels ........................ 349
6.3 DirectInhibitionoftheVesicleReleaseMachinery ............... 350
7 Endogenous Tone at Presynaptic Cannabinoid Receptors ........... 350
8 What Is the Functional Role of Presynaptic Cannabinoid Receptors? ..... 354
References ........................................ 357
AbstractThe CB 1 cannabinoid receptor is widely distributed in the central and
peripheral nervous system. Within the neuron, the CB 1 receptor is often localised
in axon terminals, and its activation leads to inhibition of transmitter release.
The consequence is inhibition of neurotransmission via a presynaptic mecha-
nism. Inhibition of glutamatergic, GABAergic, glycinergic, cholinergic, noradren-
ergic and serotonergic neurotransmission has been observed in many regions