title: Forskolin induced increase in spontaneous activity of auditory brainstem neurons is comparable to acoustic stimulus evoked responses.
abstract: Contemporary proposals for the pathophysiology of tinnitus due to cochlear damage underscore increased spontaneous activity of auditory brainstem neurons. One of the several consequences of the cochlear injury is the activation of the ERK pathway, suppression of phosphodiestase E activity, and putatively setting a long-term increase in intracellular levels of cyclic AMP at central auditory neurons. Local application of forskolin also increases intracellular cyclic AMP and spontaneous neural activity. We measured the effects of locally applied forskolin on spontaneous firing rate of isolated neurons in the peri-olivary region of the superior olive complex in anesthetized adult Long Evan rats. Forskolin induced increase in spontaneous neural activity was comparable to supra-threshold tone evoke neural responses. These results are viewed in context of hyperexcitability as a correlate of tinnitus.
authors.affiliation: Department of Neurology, Case Western Reserve University, Cleveland, OH, United States. aasefshaikh@gmail.com
authors.forename: Aasef G
authors.initials: AG
authors.lastname: Shaikh
authors.forename: Paul G
authors.initials: PG
authors.lastname: Finlayson
mesh_terms: D000161:Acoustic Stimulation; D000818:Animals; D001933:Brain Stem / Q000187:drug effects / Q000502:physiology*; D005576:Colforsin / Q000494:pharmacology; D000242:Cyclic AMP / Q000378:metabolism; D004594:Electrophysiology; D016057:Evoked Potentials, Auditory, Brain Stem / Q000187:drug effects / Q000502:physiology*; D009474:Neurons / Q000187:drug effects / Q000502:physiology*; D051381:Rats; D020318:Rats, Long-Evans; D014012:Tinnitus / Q000503:physiopathology*
chemical_list: D005576:Colforsin; D000242:Cyclic AMP