Kv3.1 is a potassium channel that functions in action potential repolarisation in fast-firing neurons. Kv3.1 is not a classic cannabinoid receptor but its activity is modulated by cannabinoids. Since cannabinoids have a physiological effect on Kv3.1 it is effectively a cannabinoid receptor.

Chemical Name: 
Potassium voltage-gated channel subfamily C member 1, KCNC1
IUPHAR entry: 
Wikipedia entry: 

Kv3.1 channels are prominently expressed in brain (cerebellum > globus pallidus, subthalamic nucleus, substantia nigra > reticular thalamic nuclei, cortical and hippocampal interneurons > inferior colliculi, cochlear and vestibular nuclei), and in retinal ganglion cells.

Literature Discussion: 



Pertwee, R.G., Howlett, A.C., Abood, M.E., Alexander, S.P.H., Di Marzo, V., Elphick, M.R., Greasley, P.J., Hansen, H.S., Kunos, G., Mackie, K., et al. (2010). International Union of Basic and Clinical Pharmacology. LXXIX. cannabinoid receptors and their ligands: beyond CB₁ and CB₂. Pharmacol. Rev. 62, 588–631.