SPECTRAL SENSITIVITY AND MECHANISM OF INTERACTION BETWEEN INHIBITORY AND EXCITATORY RESPONSES OF PHOTOSENSORY PINEAL NEURONS
SPECTRAL SENSITIVITY AND MECHANISM OF INTERACTION BETWEEN INHIBITORY AND EXCITATORY RESPONSES OF PHOTOSENSORY PINEAL NEURONS
复制标题
DOI：
10.1007/bf00374547
复制
发表时间：
1994-06-01
影响因子：
4.5
通讯作者：
MORITA, Y
中科院分区：
文献类型：
--
作者：
UCHIDA, K;MORITA, Y
对日本七鳃鳗感光器内染色型神经元的特征和分布进行了电生理学研究。神经元活动被短波长的光抑制，而被中波长至长波长的光激发。抑制和兴奋反应的最大灵敏度分别在380 nm和540 nm左右。在稳定照明10分钟的时间内的神经元的尖峰活动进行了测量。虽然短波长的闪光引起了强烈的抑制，在神经元，这种效果并没有持续在10分钟的光刺激。结果发现，抑制效果继续时，兴奋（中波长）光与抑制（短波长）光一起传递。这一结果支持了松果体光感受器中的光再生假说，即当对短波长具有高敏感性的光感受器接收中波长光时发生光再生。与抑制性反应相反，在刺激期间，由中间波长引起的兴奋性反应持续。神经元的尖峰频率由光的光谱组成决定。由于环境光包含抑制和兴奋成分，神经元将在白天保持这两种敏感性，并可以测量光谱组成的变化。从记录部位来看，染色质型神经元主要分布在松果体的外周部。
The characteristics and distribution of chromatic-type neurons in the photosensory pineal organ of the river lamprey, Lampetra japonica, were investigated electrophysiologically. Neuronal activity was inhibited by light of short wavelengths and excited by middle to long wavelengths. The maximum sensitivities of the inhibitory and excitatory responses were at about 380 nm and 540 nm respectively. The spike activity of the neurons during steady illumination for a 10-min period was measured. Although a flash of short-wavelength light caused a strong inhibition in the neuron, this effect was not sustained during 10 min of photic stimuli. It was found that the inhibitory effect continued when excitatory (middle-wavelength) light was delivered together with inhibitory (short-wavelength) light. The result supports the hypothesis of photoregeneration in the pineal photoreceptor, which occurs when photoreceptors having high sensitivity to short wavelengths receive middle-wavelength light. Contrary to the inhibitory response, the excitatory one caused by middle wavelengths continued during stimulation. Spike frequency of the neuron was determined by the spectral composition of the light. Since environmental light contains both inhibitory and excitatory components, the neuron would keep both sensitivities during the daytime and could measure the variation in the spectral composition. Judging from the recording sites, the chromatic-type neurons are distributed in the peripheral part of the pineal organ.