Cannabinoids and Sensory Neurones

DRG neurones are a heterogeneous population of neurones that vary in sensory transduction mechanisms, myelination, axon diameter, cell soma size, neurotransmitter content, receptor and ion channel expression. The generation, conduction, integration and transmission of pain signals begin in DRG neurones and they remain an important target for therapeutic intervention in pain disorders. In this review we discuss the expression of cannabinoid receptors in DRG neurones. We will also discuss the actions and molecular mechanisms of cannabinoid receptor ligands in the context of modulating sensory neurone excitability. Evidence suggests that vanilloid and cytokine receptor functions, voltageactivated Ca2+ and K + channels and Ca2+-activated channels are all either direct or indirect sites that might be modulated by synthetic and endogenous cannabinoid ligands.