Responses of giant interneurons of the cockroachPeriplaneta americana to wind puffs of different directions and velocities
Responses of giant interneurons of the cockroachPeriplaneta americana to wind puffs of different directions and velocities
复制标题
美洲大蠊巨型中间神经元对不同方向和速度的风的反应
DOI：
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发表时间：
2004
期刊：
影响因子：
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通讯作者：
J. Camhi
中科院分区：
文献类型：
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作者：
J. Westin;J. Langberg;J. Camhi
摘要1.控制不同方向和速度的风吹到蟑螂（Periplaneta americana）的尾椎，同时记录细胞内可识别的巨大中间神经元（GI）的反应。给定GI的方向灵敏度在动物之间是一致的（图7）3.改变风吹送的角度揭示了，在神经索的每一侧，两个GI（2，4）显示出很少或没有方向选择性，两个GI（1，7）对来自同侧的风具有更大的响应，两个GI（3，6）主要对来自动物前方的风作出反应，而一个GI（5）主要对来自同侧后象限的风作出反应（图7）。这些方向特性与风速无关，风速至少为2.6 m/s（图8）4.改变风刺激的峰值速度（从每个GI的最大反应角度传递）显示，对于某些GI，诱发的动作电位数量随着风速的增加而增加，风速至少为2.6 m/s（1，5，6，7），而对于其他（2，3，四、（图9）5.覆盖或去除给定GI对侧的尾索可降低每个GI的反应，而不会明显改变其方向选择性。（图11 A）。消除同侧尾索也适度降低了一些GI的反应（4，5，7），但几乎或完全消除了其他GI的反应（GI的1，2，3，6）（图11B）6. GI响应于“标准风吹”的尖峰频率（峰值速度0.6 m/s或2.6 m/s）的频率很高，维持频率通常超过每秒300个尖峰（表1），瞬时频率有时超过每秒900个尖峰（图10）7.胃肠道的方向选择性、高尖峰频率和快速传导速度可能是介导蟑螂短潜伏期、定向逃避行为的适应性。结果进行了讨论，在假定的作用GI的在这种行为和感觉统合的影响。
Summary1.Controlled wind puffs of different directions and velocities were delivered to the cerci of cockroaches (Periplaneta americana), while the responses of individually identifiable giant interneurons (GI's) were recorded intracellularly.2.All fourteen histologically identified GI's (seven bilateral pairs) respond with a burst of action potentials to wind from some or all directions. The directional sensitivity of a given GI is consistent from animal to animal (Fig. 7).3.Varying the angle of delivery of wind puffs revealed that, in each side of the nerve cord, two GI's (2, 4) show little or no directional selectivity, two GI's (1, 7) have a greater response to wind from the ipsilateral side, two GI's (3, 6) respond primarily to wind from in front of the animal, and one GI (5) responds primarily to wind from the ipsilateral rear quadrant (Fig. 7). These directional properties are independent of wind velocity up to at least 2.6 m/s (Fig. 8).4.Varying the peak velocity of the wind stimuli (delivered from each GI's maximal response angle) showed that the number of action potentials evoked increases with wind velocity up to at least 2.6 m/s for some GI's (1, 5, 6, 7), while the number does not increase with velocity beyond 0.5 m/s for others (2, 3, 4) (Fig. 9).5.Covering or removing the cercus contralateral to a given GI reduced the response of each GI without appreciably altering its directional selectivity (Fig. 11 A). Eliminating the ipsilateral cercus also moderately reduced the responses of some GI's (4, 5, 7), but nearly or completely abolished responses in others (GI's 1, 2, 3, 6) (Fig. 11B).6.The spike frequencies of the GI's in response to “standard wind puffs” (peak velocity 0.6 m/s or 2.6 m/s) are high, with maintained frequencies often over 300 spikes per s (Table 1), and instantaneous frequencies some times over 900 per s (Fig. 10).7.The directional selectivity, high spike frequency, and rapid conduction velocity of the GI's may be adaptations for mediating the short latency, directional evasive behavior of the cockroach. The results are discussed in terms of the presumed role of the GI's in this behavior and implications for sensory integration.