Umemura K, Asai Y, Hirata Y, Uematsu T, Nakashima M
Department of Pharmacology, Hamamatsu University School of Medicine, Japan.
Jpn J Pharmacol. 1993 Feb;61(2):75-9. doi: 10.1254/jjp.61.75.
The effect of ibudilast (0.1, 0.3 mg/kg), which has cerebral vasodilating and antiplatelet effects, was evaluated in two models of rat inner ear microcirculation thrombosis by using the photochemical reaction between green light (wave length: 540 nm) and intravenous injection of rose bengal. Furthermore, the inner ear blood flow was measured by a laser-Doppler flowmeter. In the hearing disturbance model, under anesthesia, the compound action potential of the cochlear nerve (AP) was measured by an electrocochleogram. The sound stimulus was an 8-kHz sine wave at 80 dB SPL. The AP was calculated 128 times. In the controls, the AP disappeared about 4 min after the intravenous injection of rose bengal (20 mg/kg). The time required to completely suppress the AP in the animals treated with ibudilast (0.1, 0.3 mg/kg) was significantly prolonged as compared with that in the controls. In the equilibrium dysfunction model, ibudilast (0.1, 0.3 mg/kg) reduced the time of abnormal swimming in the swimming test 24 hr after the completion of photo-illumination. Ibudilast (0.3 mg/kg) increased the inner ear blood flow during the 10-min observation period as compared with the controls, while it did not affect the mean blood pressure. In conclusion, ibudilast increased the inner ear blood flow and was effective in two models of rat inner ear microcirculation thrombosis.
具有脑血管舒张和抗血小板作用的异丁司特（0.1、0.3毫克/千克）的效果，通过绿光（波长：540纳米）与静脉注射孟加拉玫瑰红之间的光化学反应，在两种大鼠内耳微循环血栓形成模型中进行了评估。此外，使用激光多普勒血流仪测量内耳血流量。在听力障碍模型中，在麻醉状态下，通过耳蜗电图测量耳蜗神经复合动作电位（AP）。声音刺激为80分贝声压级的8千赫正弦波。AP计算128次。在对照组中，静脉注射孟加拉玫瑰红（20毫克/千克）后约4分钟AP消失。与对照组相比，用异丁司特（0.1、0.3毫克/千克）治疗的动物中完全抑制AP所需的时间显著延长。在平衡功能障碍模型中，异丁司特（0.1、0.3毫克/千克）缩短了光照结束后24小时游泳试验中异常游泳的时间。与对照组相比，异丁司特（0.3毫克/千克）在10分钟观察期内增加了内耳血流量，而对平均血压没有影响。总之，异丁司特增加了内耳血流量，并且在两种大鼠内耳微循环血栓形成模型中均有效。
