The effect of PAF in the cochlea of guinea pigs

The influence of 10(-10) and 10(-9) M PAF/animal given into the jugular vein over 30 sec on inner ear potentials, i.e. endolymphatic potential (EP), summating potential (SP) and cochlear microphonics (CM) was investigated. The EP showed the most pronounced changes. When infusing a specific PAF receptor antagonist, ginkgolide B, or the TXA2 receptor antagonist, sulotraban, before the the infusion of PAF, the changes in cochlear potentials could be completely prevented. A second TXA2 receptor antagonist, daltroban, did not effectively prevent PAF actions. It is hypothesized that these PAF effects are due to an interference with ion transport in the non-sensory structures of the inner ear.