Postischemic mild hypothermia alleviates hearing loss because of transient ischemia.
The effect of postischemic mild hypothermia on the inner ear has not been clarified. In this study, we investigated whether hypothermia after transient ischemia could prevent cochlear damage and its therapeutic time window. Mongolian gerbils were divided into six groups: a sham-operation group, a normothermia group, and four hypothermia groups in which hypothermia was induced 1-7, 1-4, 3-6, and 6-9 h after reperfusion. Animals subjected to postischemic mild hypothermia within 3 h after reperfusion had attenuated hearing loss and inner hair cell loss. The protective effect was greater when hypothermia was induced earlier and had a longer duration. This implies that mild hypothermia after ischemia could have therapeutic effects for inner ear ischemic damage.
Takeda
Shoichiro
S
Departments of aOtolaryngology bFunctional Historogy, Ehime University School of Medicine, Shitsukawa, Toon, Ehime, Japan.
Hakuba
Nobuhiro
N
Yoshida
Tadashi
T
Fujita
Kensuke
K
Hato
Naohito
N
Hata
Ryuji
R
Hyodo
Jun
J
Gyo
Kiyofumi
K
D000818:Animals; D002545:Brain Ischemia / Q000150:complications*; D003051:Cochlea / Q000098:blood supply / Q000473:pathology; D005849:Gerbillinae; D006199:Hair Cells, Auditory, Inner / Q000473:pathology; D034381:Hearing Loss / Q000209:etiology / Q000628:therapy*; D007036:Hypothermia, Induced; D002546:Ischemic Attack, Transient / Q000150:complications*; D015424:Reperfusion; D013997:Time Factors