Propertiesof intact photoreceptor cells lacking synapses.
Propertiesof intact photoreceptor cells lacking synapses.
复制标题
缺乏突触的完整感光细胞的特性。
DOI：
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发表时间：
1968
期刊：
影响因子：
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通讯作者：
Timothy H. Goldsmith
中科院分区：
文献类型：
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作者：
Daniel M. Eichenbaum;Timothy H. Goldsmith
通过将三龄家蝇幼虫（Musca acutica）的眼胚盘移植到宿主幼虫的眼内，等待宿主蝇的发育，获得了与中枢神经系统无联系的手术未损伤的感光细胞。分化后，移植物的感光细胞具有正常的细胞体和横纹。另一方面，它们的轴突不与高级细胞形成突触。因此，从视叶分离的小网膜细胞对照明产生电反应，该电反应与正常受体细胞的膜反应难以区分，并且在中等强度的刺激下由初始瞬变和平台组成。这种索马（受体电位）的分级去极化以电张力的方式扩散到轴突中，而不引发尖峰。CO2和河豚毒素对离体光感受器的受体电位都没有影响。移植的暗适应率与正常小网膜相同，暗适应在较长时间的光适应后较慢。显然，在果蝇中，神经节层突触的发育对于受体的正常生理发育不是必需的，并且正常眼睛的光感受器的反应可以在没有来自视叶的显著反馈控制的情况下产生。
Surgically undamaged photoreceptor cells that have no connections with the central nervous system were obtained by transplanting the eye imaginal disc of third instar housefly larvae (Musca domestica) into the abdomens of host larvae and waiting for development of the host flies. Following differentiation, the photoreceptor cells of the transplants have normal cell bodies and rhabdomeres. Their axons, on the other hand, do not make synapses with higher order cells. The retinular cells, thus isolated from the optic lobe, give electrical responses to illumination that are indistinguishable from the membrane responses of normal receptor cells, and at moderate intensities of stimulation consist of an initial transient and a plateau. This graded depolarization of the soma (receptor potential) spreads electrotonically into the axon without initiating spikes. Neither CO2 nor tetrodotoxin has an effect on the receptor potential of isolated photoreceptors. The transplants dark adapt at the same rate as normal retinulae, dark adaptation being slower following longer periods of light adaptation. Clearly in flies the development of the synapses of the lamina ganglionaris is not necessary for normal physiological development of the receptors, and the responses of the photoreceptors of normal eyes can be generated without significant feedback control from the optic lobe.