title: The endocannabinoid receptor, CB1, is required for normal axonal growth and fasciculation.
abstract: Endocannabinoids are retrograde neurotransmitters, which act upon the presynaptically located, G-protein coupled receptor CB1, to modulate synaptic transmission in the adult brain. Recently, however, a number of lines of evidence have suggested that endocannabinoid signalling may play an important role in early neuronal development. In this study, we show that the CB1 receptor has a wide expression pattern in the developing nervous system and that its expression follows neuronal differentiation in the embryo from the earliest stages. We also show that the enzymes involved in 2-AG synthesis are expressed in an overlapping manner at these stages. We further show that interfering with CB1 function using a pharmacological inhibitor causes problems in axon pathfinding and fasciculation. Similarly, CB1 gene knock down in the zebrafish by morpholino injection results in defects in axonal growth and fasciculation in these embryos. Thus CB1 function is required in the early embryo for axonal growth and fasciculation.
authors: MRC Centre for Developmental Neurobiology, King's College London, London SE1 1UL, UK.
authors: Sheona
authors: S
authors: Watson
authors: David
authors: D
authors: Chambers
authors: Carl
authors: C
authors: Hobbs
authors: Patrick
authors: P
authors: Doherty
authors: Anthony
authors: A
authors: Graham
mesh_terms: D000818:Animals; D001369:Axons / Q000502:physiology*; D063385:Cannabinoid Receptor Modulators / Q000378:metabolism* / Q000502:physiology; D002642:Chick Embryo / Q000294:innervation / Q000378:metabolism; D063388:Endocannabinoids; D009434:Neural Pathways / Q000502:physiology; D043884:Receptor, Cannabinoid, CB1 / Q000037:antagonists & inhibitors / Q000502:physiology*; D015027:Zebrafish / Q000196:embryology / Q000378:metabolism
chemical_list: D063385:Cannabinoid Receptor Modulators; D063388:Endocannabinoids; D043884:Receptor, Cannabinoid, CB1