Effect of glycerol on cochlea microcirculation.

Microcirculation in the cochlea of l2 normal anesthetized guinea pigs was investigated after intravenous infusion of 2.4 ml/kg of 40% glycerol. In these experiments endolymphatic PO2, blood pressure, cochlear microphonics, and endocochlear potentials were recorded. Administration of glycerol caused a significant increase in endocochlear PO2 for about 30 minutes. The improvement of hearing in patients with Meniere's disease is thus not only a result of the reduced hydrostatic pressure, as has been demonstrated by others, but may also be the result of vasodilatation, which improves microcirculation in the cochlea with resultant increases in endocochlear PO2.