Basta Dietmar, Ernst Arne
Department of Otolaryngology at UKB, Free University of Berlin, Warener Strasse 7, 12683 Berlin, Germany.
Neurosci Res. 2004 Oct;50(2):237-43. doi: 10.1016/j.neures.2004.07.003.
Salicylate is a well-known substance to produce reversible tinnitus in humans and animals. It has been shown that systemic application of salicylate changes the neuronal spontaneous activity in several parts of the auditory pathway. Salicylate has also a direct influence on cochlear outer hair cell electromotility. The effects observed in the central auditory structures in vivo could therefore be based upon the change in afferent cochlear input to the auditory system and in addition by a direct action of salicylate on neurons within the auditory pathway. The present study investigated the direct effect of salicylate application on the spontaneous activity of mouse inferior colliculus neurons in brain slices. Out of 92 neurons, 87% responded statistically significantly to the superfusate by changing their firing rates. 70% increased and 17% decreased their firing rates, respectively. Salicylate superfusion induced a general increase of electrophysiological activity within the inferior colliculus brain slice preparation which was similar to those obtained during systemic application of salicylate. The results suggest that the salicylate sensitivity of inferior colliculus neurons can modulate to a great extent the salicylate-induced generation of tinnitus.
水杨酸盐是一种在人类和动物中会导致可逆性耳鸣的知名物质。研究表明，全身性应用水杨酸盐会改变听觉通路多个部位的神经元自发活动。水杨酸盐还对耳蜗外毛细胞的电运动有直接影响。因此，在体内中枢听觉结构中观察到的效应可能基于传入耳蜗对听觉系统输入的变化，此外还基于水杨酸盐对听觉通路内神经元的直接作用。本研究调查了在脑片中应用水杨酸盐对小鼠下丘神经元自发活动的直接影响。在92个神经元中，87% 的神经元通过改变放电率对灌流液有统计学上显著的反应。分别有70% 的神经元放电率增加，17% 的神经元放电率降低。水杨酸盐灌流导致下丘脑片标本中的电生理活动普遍增加，这与全身性应用水杨酸盐时获得的结果相似。结果表明，下丘神经元对水杨酸盐的敏感性在很大程度上可调节水杨酸盐诱导的耳鸣产生。
