THE VESTIBULAR NERVE OF THE CHINCHILLA .5. RELATION BETWEEN AFFERENT DISCHARGE PROPERTIES AND PERIPHERAL INNERVATION PATTERNS IN THE UTRICULAR MACULA
THE VESTIBULAR NERVE OF THE CHINCHILLA .5. RELATION BETWEEN AFFERENT DISCHARGE PROPERTIES AND PERIPHERAL INNERVATION PATTERNS IN THE UTRICULAR MACULA
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DOI：
10.1152/jn.1990.63.4.791
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发表时间：
1990-04-01
影响因子：
2.5
通讯作者：
FERNANDEZ, C
中科院分区：
文献类型：
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作者：
GOLDBERG, JM;DESMADRYL, G;FERNANDEZ, C
1.利用轴突内标记技术研究了龙猫椭圆囊传入神经的放电特性与其周围神经支配模式之间的关系。将辣根过氧化物酶 (HRP) 或荧光黄 CH (LY) 注射到 53 个生理特征单元中，并将其标记过程追溯到椭圆囊黄斑。对于大多数标记的神经元，确定了放电规律、背景放电和对外部施加电流的敏感性，以及对 2 Hz 正弦线性力响应的增益 (g2 Hz) 和相位 (phi 2 Hz)。重建末端区域，并将纤维分类为花萼 (n = 13) 或二态单位 (n = 40)。没有恢复任何布顿单元。花萼单位仅限于条纹。二态性单位位于 striola (n = 8)、juxtastriola (n = 7) 或外周 extrastriola (n = 25)。 2.为了确定轴突内样本是否具有代表性，将标记的椭圆囊单位的生理特性与细胞外记录单位的较大样本的生理特性进行比较。还对轴突内标记单元的形态与通过细胞外注射 HRP 到前庭神经标记的单元的形态进行了比较。轴突内样品和细胞外样品之间的大多数差异可以通过假设小直径纤维在前一个样品中代表性不足来解释。与细胞外标记的二态性纤维相比，轴突内标记的二态性纤维具有更多的布顿末端和更大的末端树。后者的差异可能反映了细胞外材料的采样偏差。 3.花萼单位不规则地放电。二形性单位的放电规律与其黄斑位置有关。 striola 中只有 1/8 二态单元有规律地放电。在近星三叶中，该比率增加到 3/7，在外周外星三叶中，该比率增加到 23/25。在二态单元中，不规则地释放传入信号有较少的 bouton 结尾的趋势。这种趋势远非完美，因为可以选择具有相似数量的布顿但具有从规则到不规则的放电模式的二态单元的子样本。 4. 已发表的形态偏振图可用于从黄斑位置预测单元的兴奋倾斜方向。预测在 39/41 标记的传入神经中得到证实。 5. 传入神经的电敏感度 (beta *)，无论其外周神经支配模式或其上皮位置如何，与归一化变异系数 (CV*) 密切相关。（摘要截断为 400 字）
1. The relation between the discharge properties of utricular afferents and their peripheral innervation patterns was studied in the chinchilla by the use of intra-axonal labeling techniques. Fifty-three physiologically characterized units were injected with horseradish peroxidase (HRP) or lucifer yellow CH (LY) and their labeled processes were traced to the utricular macula. For most labeled neurons, the discharge regularity, background discharge, and sensitivity to externally applied galvanic currents were determined, as were the gain (g2 Hz) and phase (phi 2 Hz) of the response to 2-Hz sinusoidal linear forces. Terminal fields were reconstructed and fibers were classified as calyx (n = 13) or dimorphic units (n = 40). No bouton units were recovered. Calyx units were confined to the striola. Dimorphic units were located in the striola (n = 8), the juxtastriola (n = 7), or the peripheral extrastriola (n = 25). 2. To determine whether the intra-axonal sample was representative, the physiological properties of labeled utricular units were compared with those of a larger sample of extracellularly recorded units. A comparison was also made between the morphology of intra-axonally labeled units and those labeled by the extracellular injection of HRP into the vestibular nerve. Most of the discrepancies between the intra-axonal and either extracellular sample can be explained by assuming that small-diameter fibers are underrepresented in the former sample. Dimorphic fibers labeled intra-axonally had more bouton endings and larger terminal trees than did those labeled extracellularly. The latter differences may reflect a sampling bias in the extracellular material. 3. Calyx units were irregularly discharging. The discharge regularity of dimorphic units was related to their macular locations. Only 1/8 dimorphic units in the striola was regularly discharging. The ratio increases to 3/7 in the juxtastriola and to 23/25 in the peripheral extrastriola. Among dimorphic units, there is a tendency for irregularly discharging afferents to have fewer bouton endings. The trend is far from perfect because it is possible to pick a subsample of dimorphic units that have similar numbers of boutons and, yet, have discharge patterns that range from regular to irregular. 4. Published morphological polarization maps can be used to predict the excitatory tilt directions of a unit from its macular location. Predictions were confirmed in 39/41 labeled afferents. 5. The galvanic sensitivity (beta *) of an afferent, irrespective of its peripheral innervation pattern or its epithelial location, was strongly correlated with a normalized coefficient of variation (CV*).(ABSTRACT TRUNCATED AT 400 WORDS)