Korean J Otolaryngol-Head Neck Surg.  1998 May;41(5):553-558.

Changes of the Ca2+ Current of the Cochlear Outer Hair Cells by Cisplatin in Guinea Pigs

• Chung JW
• Kim CS

Abstract

BACKGROUND AND OBJECTIVES: The mechanism of cisplatin ototoxicity has been well studied and several evidences indicating outer hair cell damage have been found. Calcium plays an important role in cellular signal transduction and many studies argued that calcium channel was blocked or modified by ototoxic drug. Authors aimed to determine the changes of calcium channel regulation by cisplatin in isolated outer hair cells, and to speculate the mechanism of hearing loss by cisplatin.
MATERIALS AND METHODS
Outer hair cells were isolated from guinea pigs by enzymatic and mechanical dissociation. Calcium current was recorded by whole cell patch clamp method and any changes in the calcium current were observed after cisplatin (0.3 mM) perfusion in bath solution.
RESULTS
In outer hair cells, calcium current (I(Ca)) and barium current (I(Ba)) were L-type current and IBa was blocked completely by bath application of cisplatin over the whole range of test potentials.
CONCLUSION
From the above results, we suggested that cisplatin ototoxicity may be due to the inhibition of calcium current and it can be speculated that disturbance of Ca2+ regulation mechanism may play a role in the provocation of hearing loss in cisplatin ototoxicity.

Keyword

Calcium current; Cisplatin ototoxicity; Whole cell patch clamp; Signal transduction mechanism

MeSH Terms

Animals
Barium
Baths
Calcium
Calcium Channels
Cisplatin*
Guinea Pigs*
Guinea*
Hair*
Hearing Loss
Perfusion
Signal Transduction
Barium
Calcium
Calcium Channels
Cisplatin