Korean J Otolaryngol-Head Neck Surg.  2000 Aug;43(8):799-803.

Effects of Platelet Activating Factor (PAF) on Cochlear Blood Flow in Guinea Pigs

• Cho YS
• Park JH
• Kim JS
• Lim HJ

Abstract

BACKGROUND AND OBJECTIVES: Platelet-activating factor (PAF) has been reported to be an active mediator of inflammation and ischemic damage in many organs. It plays a significant role in the pathogenesis of middle ear effusion. However, there have been few reports concerning the effects of PAF on inner ear and inner ear blood flow. This study determined the effects of PAF on the relation of cochlear blood flow (CBF) in guinea pigs.
MATERIALS AND METHODS
The round window membrane (RWM) in each of 26 guinea pigs was exposed by dorsal approach and PAF was applied on it by Gelfoam pledgets. CBF of the basal turn was monitored using a laser Doppler flowmetry with the systemic blood pressure and changes in CBF being monitored, recorded and analysed. Epinephrine and normal saline were applied in the same manner as positive and negative controls, respectively.
RESULTS
CBF was significantly reduced by the epinephrine application as a positive control. PAF applied at a concentration of 10 microgram/ml significantly increased CBF, while PAF applied at a concentration of 200 microgram/ml significantly reduced CBF.
CONCLUSION
PAF did not induce ischemic damages when applied in the same concentration as the middle ear effusion fluid. However, when PAF was applied in excess, cochlear ischemia might be one of the mechanisms of inner ear damage it causes.

Keyword

Platelet activating factor; Cochlea; Regional blood tlow

MeSH Terms

Animals
Blood Platelets*
Blood Pressure
Cochlea
Ear, Inner
Epinephrine
Gelatin Sponge, Absorbable
Guinea Pigs*
Guinea*
Inflammation
Ischemia
Laser-Doppler Flowmetry
Membranes
Otitis Media with Effusion
Platelet Activating Factor*
Epinephrine
Platelet Activating Factor