Vol.101 No.9 contentsPRACTICA OTO-RHINO-LARYNGOLOGICA
Vol. 101 No. 9 September 2008
Meniere's Disease and Stress
-An Involvement of the Vasopressin-aquaporin2 System in the Inner Ear-
Taizou Takeda
(Nishinomiya Municipal Central Hospital)
Akinobu Kakigi
(Kochi Medical School)
Recently, there has been considerable evidence suggesting the hormonal control of the inner ear. The vasopressin-aquaporin2 (VP-AQP2) system may play an important role in the regulation of water in the inner ear. Endolymphatic hydrops, over-accumulation of endolymph, is thought to result from the mal-regulation of the VP-AQP2 system in inner ear fluid. We reported that plasma VP (p-VP) levels were elevated in Meniere's disease and that elevation was noted in cases of Meniere's disease with emotional or physical stress. Since stress is well-known to lead to excessive secretion of VP, it is likely that a stress-associated rise in p-VP causes a disturbance of the VP-AQP2 system in the inner ear, resulting in vertiginous attacks and/or aggravation of hearing in Meniere's disease. This paper reviews the clinical and experimental evidence supporting the novel view that endolymphatic hydrops, the morphological characteristics of Meniere's disease, reflects the mal-regulation of the VP-AQP2 system in inner ear fluid, and that a stress-associated rise in p-VP is one of the causative factors of vertigo and deafness in Meniere's disease.
Key words :Meniere's disease, endolymphatic hydrops, vasopressin, aquaporin-2, V2-receptor, V2-antagonist, OPC-31260