Didier A, Cazals Y
Laboratoire d'Audiologie expérimentale, INSERM-U 229, Université Bordeaux II, France.
Hear Res. 1989 Jan;37(2):123-7. doi: 10.1016/0378-5955(89)90034-8.
Previous studies have demonstrated the existence of acoustic responses from the saccule in guinea pigs for stimulus intensities above 75 dB SPL. It is well known that the saccule receives a double afferent innervation: a bundle of the superior branch of the eighth nerve reaches its anterior part and another bundle of the inferior branch innervates its posterior part. These two bundles join just at the exit of the internal auditory meatus. An electrophysiological experiment was performed to investigate whether saccular acoustic responses could be similarly recorded from both bundles. Recordings from an electrode tip of 0.2 mm diameter were obtained in normal animals and also in animals with a complete and selective destruction of the cochlear sensory epithelium induced by treatment with an ototoxic antibiotic combined with a loop diuretic. In both normal and treated animals acoustic responses with the peculiar very short latency were specifically recorded in the area of the junction of the two bundles, they were of maximal amplitude on the bundle of the inferior branch. These data confirm in a more direct way the saccular origin of the short latency acoustic responses and indicate that they are probably conveyed in both saccular nerve bundles but mostly in that of the inferior branch of the eighth nerve. Finally these data show unequivocally that saccular acoustic responses exist in normal guinea pig ears.
先前的研究已经证明，对于强度高于75 dB SPL的刺激，豚鼠球囊存在听觉反应。众所周知，球囊接受双重传入神经支配：第八神经上支的一束神经到达其前部，另一束下支神经支配其后部。这两束神经恰好在内耳道出口处汇合。进行了一项电生理实验，以研究是否能从这两束神经中类似地记录到球囊听觉反应。在正常动物以及用耳毒性抗生素联合襻利尿剂处理诱导耳蜗感觉上皮完全且选择性破坏的动物中，从直径为0.2 mm的电极尖端进行记录。在正常动物和处理过的动物中，在两束神经汇合区域均特异性记录到了具有特殊极短潜伏期的听觉反应，在下支神经束上其幅度最大。这些数据以更直接的方式证实了短潜伏期听觉反应的球囊起源，并表明它们可能通过两束球囊神经束传导，但主要通过第八神经下支的神经束传导。最后，这些数据明确表明正常豚鼠耳中存在球囊听觉反应。
