Functional and morphological changes of the cochlea in guinea pigs during anoxia

The influence to endocochlear potential (EP), cochlear microphonics (CM) and summating potential (SP), the ultrastructural changes of the cochlea and the survival time of hair cells in guinea pigs during anoxia and suffocation were investigated. We found that: 1) The stria vascularis was much more sensitive to anoxia than hair cells. 2) 85% CM was highly sensitive to anoxia, and 15% kept stable until the destruction of outer hair cells. 3) -SP turned into +SP after anoxia. 4) EP was related to the destruction of outer hair cells and the disappearance of CM.