レーザードップラー法によるモルモット内リンパ嚢血流と蝸牛血流の測定

抄録

The endolymphatic sac blood flow (ESBF) and cochlear blood flow (CBF) in normal guinea pigs were measured by laser-Doppler flowmetry (Advance Laser Flowmeter, Model ALF 2100) following intravenous administration of 70% isosorbide (1.6ml/kg), 50% glycerol (2.4ml/kg) or diphenidol hydrochloride (10mg/kg) under general anesthesia with intraperitoneal injection of pentobarbital sodium. Respiration was controlled by a respirator after tracheotomy and blood pressure was monitored through the femoral artery (Gould Statham P23 ID Pressure Transducer). For ESBF measurements, a probe was placed on the right endolymphatic sac after entering the posterior fossa via the dorsal approach. For CBF measurements, a probe was placed on the basal turn of the right cochlea via the ventral approach. Isosorbide, glycerol or diphenidol hydrochloride was administered respectively through the jugular vein for 60 seconds. Both ESBF and CBF increased immediately after administration of isosorbide or glycerol, reached a peak within 2-5 minutes and decreased gradually to the initial baseline levels in 12-18 minutes. On the contrary, diphenidol hydrochloride induced a reduction of both ESBF and CBF. Blood flow changes were usually corresponded to systemic blood pressure changes. The magnitude of the CBF response in these 3 different drugs tended to be slightly greater than that of the ESBF response. This may be resulted from the anatomical difference of each blood supply i.e. CBF from the vertebrobasilar artery and ESBF from the external carotid artery.