Cochlear blood flow and labyrinthine pressure: effects of glycerol on the inner ear.
Changes in cochlear blood circulation (CoBC) and perilymphatic pressure (Pp) after administration of physiological saline and 50% glycerol (12 ml/kg) were measured simultaneously in guinea pigs to examine the influence of glycerol on CoBC and Pp. The CoBC was measured by the laser-Doppler method. Although neither CoBC nor Pp changed after administration of physiological saline, glycerol produced a marked increase in CoBC and a slight decrease in Pp in 11 of 15 animals. However, the increase in CoBC was transient; CoBC reached a peak as soon as 30 min after glycerol administration and then returned rapidly to its initial value within 1 h after administration, although the Pp was still decreasing. Therefore, the response of CoBC to glycerol does not seem to be directly related to hyperosmolarity due to glycerol administration.
Takeda
T
T
Department of Otolaryngology, Kochi Medical School, Japan.
Takeuchi
S
S
Kimura
T
T
Saito
H
H
D000818:Animals; D001783:Blood Flow Velocity; D001810:Blood Volume; D003051:Cochlea / Q000098:blood supply*; D007758:Ear, Inner / Q000187:drug effects* / Q000502:physiology; D005990:Glycerol / Q000494:pharmacology*; D006168:Guinea Pigs; D017078:Laser-Doppler Flowmetry; D010498:Perilymph / Q000502:physiology*; D011312:Pressure; D012039:Regional Blood Flow
D005990:Glycerol