Abstract • Cochlear microcirculation was studied with oxygen-sensitive microelectrodes simultaneously in all three scalas during anoxia, hyperoxia, and hypercapnia. The anoxia caused a sharp decline of Po2 in the scala media (SM), scala vestibuli (SV), and scala tympani (ST). Hyperoxia and hypercapnia resulted in an elevation of Po2 in all three scaias. During anoxia, the SM showed the earliest and largest decline in Po2, with the shortest recovery and reoxygenation time. When Po2 slopes (during anoxia) were compared, the SM to ST and the SM to SV were substantially different and remained different even when the partial pressures of oxygen quantified as oxygen in nanomoles. Our experiments also showed that changes in Po2 within the SM closely correlate with changes of endocochlear potential and BP. (Arch Otolaryngol 1982;108:539-543) References 1. Snow JB, Suga F: Labyrinthine vasodilator . Arch Otolaryngol 1973;97:365-370.Crossref 2. Jackson RT, Clairmont AA, Pollock RA: The effect of carbon dioxide inhalation on cerebral blood flow: A two-hour duration study in dogs with microspheres . Stroke 1974;5:344-349.Crossref 3. Hultcrantz E: The cochlear blood flow . Acta Universitatis Upsaliensis 1978;314:1-35. 4. Misrahy GA, Hildreth KM, Shinabarger EQ, et al: Endolymphatic oxygen tension in the cochlea of the guinea pig . J Acoust Soc Am 1958; 30:247-249.Crossref 5. Lawrence M, Nuttall AL, Burgio PA: Cochlear potentials and oxygen associated with hypoxia . Ann Otol Rhinol Laryngol 1975;84:499-511. 6. Fisch V, Murata K, Hossli G: Measurement of oxygen tissue in human perilymph . Acta Otolaryngol 1976;81:278-283.Crossref 7. Maass B, Baumgartl H, Lübbers DW: Lockale Po, und pH2-messungen mit nadelelekroden zum studium der sauerstoffversorgung und mikrozirkulation des innenohres . Arch Otorhino-Laryngol 1976;214:109-124.Crossref 8. Prazma J, Fischer ND, Biggers WP, et al: A correlation of the effect of normoxia, hyperoxia and anoxia on Po, of endolymph and cochlear potentials . Hear Res 1978;1:3-10.Crossref 9. Prazma J, Smith D, Jochem WJ: Current to voltage converter for measurement of oxygen . J Appl Physiol 1978;44:977-980. 10. Fernandez C: Dimensions of the cochlea (guinea pig) . J Acoust Soc Am 1952;24:519-523.Crossref 11. Voldřich L: Volumes of cochlea cavities in guinea pig . Arch Anat Histol Embryol 1967;53:96-97. 12. Okumura H: Perilymph as a medium of oxygen supply for the organ of Corti . Arch Klin Exp Ohr Nas Kehlkopfheiek 1970;195:257-265.Crossref 13. Lawrence M, Nuttall AL, Burgio PA: Oxygen reserve and autoregulation in the cochlea . Acta Otolaryngol 1977;83:146-152.Crossref 14. Norman JN, Irvin TT, MacIntyre J, et al: The effect of oxygen on the normal and the under perfused canine kidney . Br J Surg 1970;57:299-301.Crossref 15. Klabunde RE, Johnson PC: Capillary velocity and tissue Po2 changes during reactive hyperemia in skeletal muscle . Am J Physiol 1977; 233:4379-4383.
Archives of Otolaryngology – American Medical Association
Published: Sep 1, 1982