Cannabinoids, cannabinoid receptors and tinnitus

Hear Res. 2016 Feb;332:210-216. doi: 10.1016/j.heares.2015.09.014. Epub 2015 Oct 1.

Abstract

One hypothesis suggests that tinnitus is a form of sensory epilepsy, arising partly from neuronal hyperactivity in auditory regions of the brain such as the cochlear nucleus and inferior colliculus. Although there is currently no effective drug treatment for tinnitus, anti-epileptic drugs are used in some cases as a potential treatment option. There is increasing evidence to suggest that cannabinoid drugs, i.e. cannabinoid receptor agonists, can also have anti-epileptic effects, at least in some cases and in some parts of the brain. It has been reported that cannabinoid CB1 receptors and the endogenous cannabinoid, 2-arachidonylglycerol (2-AG), are expressed in the cochlear nucleus and that they are involved in the regulation of plasticity. This review explores the question of whether cannabinoid receptor agonists are likely to be pro- or anti-epileptic in the cochlear nucleus and therefore whether cannabinoids and Cannabis itself are likely to make tinnitus better or worse.

Keywords: Cannabidiol (CBD); Cannabinoid receptors; Cannabinoids; Delta-6-THC; Tinnitus.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Animals
  • Anticonvulsants / adverse effects
  • Auditory Pathways / drug effects
  • Auditory Pathways / metabolism
  • Auditory Pathways / physiopathology
  • Cannabinoid Receptor Agonists / adverse effects
  • Cannabinoids / metabolism*
  • Cochlear Nucleus / drug effects
  • Cochlear Nucleus / metabolism*
  • Cochlear Nucleus / physiopathology
  • Endocannabinoids / metabolism*
  • Humans
  • Neuronal Plasticity
  • Receptors, Cannabinoid / drug effects
  • Receptors, Cannabinoid / metabolism*
  • Tinnitus / diagnosis
  • Tinnitus / drug therapy
  • Tinnitus / metabolism*
  • Tinnitus / physiopathology

Substances

  • Anticonvulsants
  • Cannabinoid Receptor Agonists
  • Cannabinoids
  • Endocannabinoids
  • Receptors, Cannabinoid