Altered taste responses in adult NST after neonatal chorda tympani denervation.
Altered taste responses in adult NST after neonatal chorda tympani denervation.
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新生儿鼓索去神经后成人 NST 的味觉反应发生改变。
DOI：
10.1152/jn.1999.82.5.2565
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发表时间：
1999
期刊：
影响因子：
--
通讯作者：
Travers,SP
中科院分区：
文献类型：
--
作者：
Dinkins,ME;Travers,SP
外周去传入后味觉系统的解剖学和行为学变化已被观察到，但其生理后果尚不清楚。有趣的是，最近的一项行为研究表明，周围去神经可以诱导中枢可塑性。在新生鼠鼓索横断(CT)后，成年大鼠表现出明显的偏好一种通常避免的盐，NH4Cl。在本研究中，记录了类似CT去神经支配的大鼠孤束核(NST)的味觉反应，以探讨这种行为现象的生理基础。我们推测，剩余传入神经的功能连接性的改变可能是行为改变的基础。具体地说，如果以前由钠选择性CT纤维激活的NST神经元被更宽调的舌咽(GL)传入所驱动，那么SALT反应的神经编码将会改变。这样的变化应该伴随着视觉表征的变化和NH4Cl反应的增加。这一假设没有得到支持。CT去神经后，大鼠耳廓结构无明显变化，NH4Cl反应性下降，未见其他可简单解释行为效应的改变。事实上，CT去神经最显著的后果是减少了68%的氯化钠反应，这支持了以前的证据，即这种神经在编码钠盐方面发挥了关键作用。此外，我们还发现，去传入后的“重组”变化与其他感觉系统中观察到的变化相似，尽管幅度较小。刺激由GL和岩浅大神经支配的受体亚群引起的反应有增加的趋势。此外，鼻切牙管反应细胞的自发率显著增加。这种对自发频率的影响与CT麻醉相反，提示急性和慢性去神经对中枢味觉神经元的影响可能不同。总而言之，延髓水平的味觉系统似乎比其他感觉系统更能抵抗大规模的可塑性，但仍然会对失去的传入做出反应。由于在其他感觉通路的皮质水平记录到最强烈的可塑性变化，新生儿CT横切的行为效应的底物可能位于味觉系统更中心的位置。
Anatomic and behavioral changes have been observed in the taste system after peripheral deafferentation, but their physiological consequences remain unknown. Interestingly, a recent behavioral study suggested that peripheral denervation could induce central plasticity. After neonatal chorda tympani (CT) transection, adult rats demonstrated a marked preference for a normally avoided salt, NH4Cl. In the present study, taste responses were recorded from the nucleus of the solitary tract (NST) in similarly CT-denervated rats to investigate a physiological basis for this behavioral phenomenon. We hypothesized that alterations in functional connectivity of remaining afferent nerves might underlie the behavioral change. Specifically, if NST neurons formerly activated by sodium-selective CT fibers were instead driven by more broadly tuned glossopharyngeal (GL) afferents, neural coding of salt responses would be altered. Such a change should be accompanied by a shift in orotopic representation and increased NH4Cl responses. This hypothesis was not supported. After CT denervation, orotopy was unaltered, NH4Cl responsiveness declined, and no other changes occurred that could simply explain the behavioral effects. Indeed, the most pronounced consequence of CT denervation was a 68% reduction in NaCl responses, supporting previous evidence for a critical role of this nerve in coding sodium salts. In addition, we found “reorganizational” changes similar to, albeit smaller than, those observed in other sensory systems after deafferentation. There was a trend for increased responses elicited by stimulation of receptor subpopulations innervated by the GL and greater superficial petrosal nerves. In addition, the spontaneous rate of nasoincisor duct-responsive cells increased significantly. This effect on spontaneous rate is opposite to that produced by CT anesthesia, suggesting that acute versus chronic denervation may affect central taste neurons differently. In conclusion, the taste system at the medullary level seems more resistant to large-scale plasticity than other sensory systems, but nevertheless reacts to lost afferent input. Because the most robust plastic changes have been documented at cortical levels in other sensory pathways, the substrate for the behavioral effect of neonatal CT transection may be located more centrally in the gustatory system.
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双侧鼓索或舌咽神经切断后的盐味辨别。
DOI：
10.1152/ajpregu.1992.263.1.r169
发表时间：
1992
期刊：
The American journal of physiology
影响因子：
--
作者：
Spector,AC;Grill,HJ
通讯作者：
Grill,HJ
影响因子：
2.9
作者：
M. Takemura;Atsutoshi Tsujio;K. Iwase;T. Shimada;Y. Shigenaga
通讯作者：
M. Takemura;Atsutoshi Tsujio;K. Iwase;T. Shimada;Y. Shigenaga
大鼠岩大浅神经响应上腭化学刺激的神经活动
影响因子：
3.5
作者：
M. S. Nejad
通讯作者：
M. S. Nejad
DOI：
10.1085/jgp.84.2.221
发表时间：
1984-08
期刊：
The Journal of general physiology
影响因子：
--
作者：
Travers SP;Smith DV
通讯作者：
Smith DV
影响因子：
13.9
作者：
N. Weinberger
通讯作者：
N. Weinberger