Physiological properties of central amygdala neurons:: species differences
Physiological properties of central amygdala neurons:: species differences
复制标题
DOI：
10.1046/j.0953-816x.2001.01879.x
复制
发表时间：
2002-02-01
影响因子：
3.4
通讯作者：
Paré, D
中科院分区：
文献类型：
--
作者：
Dumont, ÉC;Martina, M;Paré, D
边缘系统结构的连接在物种之间是非常恒定的。然而，不同的物种以不同的方式表达恐惧。由于中央杏仁核被认为是恐惧反应的重要介质，我们比较了豚鼠，大鼠和猫的中央杏仁核神经元的生理特性，在体外冠状切片全细胞记录。在豚鼠中，大多数中央内侧和外侧神经元表现出向外整流，延迟放电起始响应去极化电流脉冲（因此命名为迟发神经元）。迟发神经元也普遍存在于猫中央核的外侧部分。相反，晚发神经元在大鼠中央核和猫中央内侧核是罕见的。在那里，大多数神经元产生的Ni 2+敏感的低阈值突发Na+尖峰和/或显示明显的向内整流超极化方向。也观察到被动特性的种属差异，但它们主要与晚发细胞的相对流行有关。事实上，与其他类型的中枢神经元相比，迟发细胞具有显著更低的输入电阻和更负的膜电位。因此，在中枢神经元的生理特性方面存在明显的物种差异。由于神经元的突触反应受到其生理特性的限制，我们的研究结果提出了一种可能性，即在不同物种中观察到的对比行为反应部分取决于中枢神经元的物种特异性生理特性。
The connections of limbic structures are remarkably constant across species. However, different species express fear in distinct ways. Because the central amygdaloid nucleus is considered an important mediator of fear responses, we compared the physiological properties of central amygdala neurons in guinea pigs, rats and cats using whole-cell recordings in coronal slices in vitro. In guinea pigs, most central medial and lateral neurons displayed an outward rectification that delayed firing onset in response to depolarizing current pulses (hence the designation late-firing neurons). Late-firing neurons were also prevalent in the lateral sector of the cat central nucleus. In contrast, late-firing neurons were rare in the rat central nucleus and the cat central medial nucleus. There, most neurons generated Ni2+-sensitive low-threshold bursts of Na+ spikes and/or displayed pronounced inward rectification in the hyperpolarizing direction. Species differences in passive properties were also observed, but they were mainly related to the relative prevalence of late-firing cells. Indeed, late-firing cells had a significantly lower input resistance and more negative membrane potential than other types of central neurons. Thus, there are marked species differences in the physiological properties of central neurons. Because the synaptic responsiveness of neurons is constrained by their physiological properties, our findings raise the possibility that the contrasting behavioural responsiveness observed across species is partly dependent on the species-specific physiological properties of central neurons.