Cav1 is a family of calcium channels of the L-type that are involved in many basic signalling processes in brain and muscle. Cav1's are not classic Cannabinoid receptors but their activity is modulated by cannabinoids. Since cannabinoids have a physiological effect on Cav1's they are effectively Cannabinoid receptors.
Basal ganglia (caudate nucleus, pallidum > putamen), cerebral cortex, hippocampus, substantia nigra, spinal cord. Cerebrum, cerebellum, spinal cord, dorsal root ganglia, lung, small intestine, testis. Skeletal muscle (predominantly transverse tubules) > bone marrow.
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.