Expression of osmotic stress protein 94 in murine endolymphatic hydrops model

Abstract

Conclusion: The up-regulation of osmotic stress protein 94 (OSP94) in the murine endolymphatic hydrops (EH) models suggests that OSP94 might be involved in cellular adaptation in response to ionic and osmotic stress in the murine inner ear. Objectives: The purpose of the present study was to investigate the expression of OSP94 in cochlear tissues of the murine EH models and control animals. Methods: Nine adult BALB/c mice were treated with both intratympanic injection of lipopolysaccharide and intraperitoneal administration of aldosterone to induce EH. Nine mice were used as control animals. The expression level of OSP94 in the EH and control groups was compared using immunohistochemistry and real-time RT-PCR. Results: Immunohistochemical staining of tissues in the EH group showed an up-regulation of OSP94 expression in the cochlea, especially in the stria vascularis and Reissner's membrane. Quantitative real-time PCR analysis also showed that transcription of the OSP94 gene in the cochlea was significantly up-regulated in the EH group.

Keywords::

• Heat-shock protein
• stria vascularis
• Reissner's membrane
• ionic homeostasis
• osmotic homeostasis

Acknowledgments

The authors thank Dr Yehoash Raphael and Lisa Beyer of Kresge Hearing Research Institute (KHRI), University of Michigan for advice and technical help. This work was supported by grant no. 04-2009-012 from Seoul National University Hospital Research Fund and a clinical research grant provided by Seoul National University Boramae Medical Center.

Declaration of interest: The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.