Eybalin M, Ripoll C
I.N.S.E.R.M., U n. 254, C.H.R. Hôpital Saint-Charles, Montpellier.
C R Acad Sci III. 1990;310(13):639-44.
Immunoreactions to a monoclonal antibody raised against parvalbumin, a calcium-binding protein, have been detected in the inner hair cells of the organ of Corti and in the spiral ganglion neurons connected to them (type I neurons). Both cell types probably use an excitatory amino acid as a neurotransmitter (glutamate and/or aspartate). No immunoreactivity was found within the second sensory cell type (outer hair cells) nor in the olivocochlear (efferent) fibers or endings in the cochlea. In the central nervous system, parvalbumin may be involved in calcium-dependent mechanisms leading to neurotransmitter release. It could thus be hypothesized that parvalbumin also have similar implications at the level of the inner hair cell and type I neuron synapses. Additional functions could also be hypothesized for this protein in the cochlea. Within the inner hair cells, parvalbumin may be involved in the ionic regulation following potassium entry during the transduction process. Within type I neurons, by buffering sudden increases in the intracellular calcium concentration, it may allow an adaptation of the firing rate to variations in the intensity of sound stimuli.
在柯蒂氏器的内毛细胞以及与其相连的螺旋神经节神经元（I型神经元）中，已检测到针对钙结合蛋白小清蛋白产生的单克隆抗体的免疫反应。这两种细胞类型可能都使用兴奋性氨基酸作为神经递质（谷氨酸和/或天冬氨酸）。在第二种感觉细胞类型（外毛细胞）以及耳蜗中的橄榄耳蜗（传出）纤维或末梢中未发现免疫反应性。在中枢神经系统中，小清蛋白可能参与导致神经递质释放的钙依赖性机制。因此可以推测，小清蛋白在内毛细胞和I型神经元突触水平上也具有类似作用。也可以推测该蛋白在耳蜗中还有其他功能。在内毛细胞内，小清蛋白可能参与转导过程中钾离子进入后的离子调节。在I型神经元内，通过缓冲细胞内钙浓度的突然升高，它可能使放电频率适应声音刺激强度的变化。
