Biophysical and morphological properties of parasympathetic neurons controling the parotid and von Ebner salivary glands in rats
Biophysical and morphological properties of parasympathetic neurons controling the parotid and von Ebner salivary glands in rats
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DOI：
10.1152/jn.00277.2004
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发表时间：
2005-02-01
影响因子：
2.5
通讯作者：
Bradley, RM
中科院分区：
文献类型：
--
作者：
Fukami, H;Bradley, RM
唾液下核(ISN)含有控制腮腺和von Ebner唾液腺的副交感神经元。为了表征这些神经元的神经生理和形态特征，我们对大鼠脑片上的ISN神经元进行了细胞内记录。神经元也被荧光黄填充并进行形态计量学分析。根据对膜超极化和去极化的反应，定义了三种类型的腮腺神经元的重复放电模式。超极化改变了对膜去极化的规则的、重复的放电反应，导致动作电位序列中第一个峰的出现延迟或第一个峰间期的长度增加。膜超极化对部分神经元的放电模式影响不大。在von Ebner唾液腺的神经元中也发现了类似的反应放电模式，其中还包括另一组用短时间爆发的动作电位做出反应的神经元。支配腮腺的神经元在形态上与von Ebner唾液腺不同，其胞体明显大于von Ebner唾液腺，树突明显多于von Ebner腺神经元。此外，腮腺神经元的平均膜输入电阻、时间常数和峰半宽显著低于von Ebner腺神经元。这些固有膜性质和形态上的差异可能与von Ebner和腮腺的功能有关。冯·埃布纳的腺体参与味觉刺激的传递和舌后乳头的清除，而腮腺则为整个口腔提供唾液。
The inferior salivatory nucleus (ISN) contains parasympathetic neurons controlling the parotid and von Ebner salivary glands. To characterize the neurophysiological and morphological properties of these neurons, intracellular recordings were made from anatomically identified ISN neurons in rat brain slices. Neurons were also filled with Lucifer yellow and morphometrically analyzed. Based on responses to membrane hyperpolarization followed by depolarization, three types of repetitive discharge patterns were defined for neurons innervating the parotid gland. The regular, repetitive discharge response to membrane depolarization was changed by hyperpolarization resulting either in a delay in the occurrence of the first spike or to an increase in the length of the first interspike interval in the action potential train. Membrane hyperpolarization had little effect on the discharge pattern of some neurons. Similar response discharge patterns were found for neurons innervating the von Ebner salivary gland, which also included a further group of neurons that responded with a short burst of action potentials. Neurons innervating the parotid salivary glands differed morphologically from the von Ebner salivary glands having significantly larger soma and more and longer dendrites than von Ebner gland neurons. In addition, the mean membrane input resistance, time constant, and spike half-width of parotid gland neurons was significantly lower than in von Ebner gland neurons. These differences in intrinsic membrane properties and morphology may relate to the functions of the von Ebner and parotid glands. von Ebner glands are involved in taste stimulus delivery and removal from posterior tongue papillae while the parotid glands contribute saliva to the entire mouth.