The Endocannabinoid System in the Cochlear Nucleus and Its Implications for Tinnitus Treatment

  • Paul F. SmithEmail author


  1. 1.

    One of the main theories of tinnitus is that it is a form of sensory epilepsy, sometimes arising from neuronal hyperactivity in the brainstem cochlear nucleus.

  2. 2.

    Antiepileptic drugs have therefore been explored as one potential treatment option.

  3. 3.

    Increasing evidence suggests that cannabinoid drugs can also have antiepileptic effects.

  4. 4.

    Recently, it has been reported that cannabinoid CB1 and CB2 receptors and the endogenous cannabinoid, 2-arachidonylglycerol (2-AG), are expressed in the cochlear nucleus.

  5. 5.

    CB1 receptors appear to negatively regulate the release of glutamate, and it is possible that their down-regulation during the development of tinnitus is responsible for the neuronal hyperactivity associated with the condition.

  6. 6.

    This chapter explores the possibility that cannabinoid drugs might be useful in the treatment of tinnitus.



Tinnitus Cochlear nucleus Cannabinoid receptors Endocannabinoids 





CB1 receptor agonist




Cochlear nucleus




Diacylglycerol lipase


Dorsal cochlear nucleus


Fatty acid amide hydrolase


Gamma-amino butyric acid


Inhibitory post-synaptic currents


Long-term depression


Long-term potentiation


Monoacylglycerol lipase






Post-synaptic potentials


Standard cannabis extracts


Ventral cochlear nucleus



This research was generously supported by the Jean Cathie Estate.


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Copyright information

© Springer Science+Business Media, LLC 2011

Authors and Affiliations

  1. 1.Department of Pharmacology and Toxicology, School of Medical SciencesUniversity of Otago Medical SchoolDunedinNew Zealand

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