van Hateren J H
J Comp Physiol A. 1986 Jun;158(6):795-811. doi: 10.1007/BF01324822.
A new method of microstimulation of the blowfly eye using corneal neutralization was applied to the 6 peripheral photoreceptor cells (R1-R6) connected to one neuro-ommatidium (and thus looking into the same direction), whilst the receptor potential of a dark-adapted photoreceptor cell was recorded by means of an intracellular microelectrode. Stimulation of the photoreceptor cells not impaled elicited responses in the recorded cell of about 20% of the response elicited when stimulating the recorded cell. This is probably caused by gap junctions recently found between the axon terminals of these cells. Stimulation of all 6 cells together yielded responses that were larger and longer than those obtained with stimulation of just the recorded cell, and intensity-response curves that deviated more strongly from linearity. Evidence is presented that the resistance of the axon terminal of the photoreceptor cells quickly drops in response to a light flash, depending on the light intensity. Incorporating the cable properties of the cell body and the axon, the resistance of the gap junctions, and the (adapting) terminal resistance, a theoretical model is presented that explains the measurements well. Finally, it is argued that the gap junctions between the photoreceptor cells may effectively uncouple the synaptic responses of the cells by counteracting the influence of field potentials.
一种利用角膜中和对家蝇眼睛进行微刺激的新方法被应用于与一个神经小眼相连（从而看向同一方向）的6个外周光感受器细胞（R1 - R6），同时通过细胞内微电极记录暗适应光感受器细胞的感受器电位。对未刺入的光感受器细胞进行刺激时，记录细胞产生的反应约为刺激记录细胞时产生反应的20%。这可能是由最近在这些细胞的轴突末端发现的缝隙连接引起的。同时刺激所有6个细胞产生的反应比仅刺激记录细胞时更大、持续时间更长，并且强度 - 反应曲线与线性的偏差更大。有证据表明，光感受器细胞的轴突末端电阻会根据光强度对光闪光迅速下降。结合细胞体和轴突的电缆特性、缝隙连接的电阻以及（适应的）末端电阻，提出了一个理论模型，该模型能很好地解释这些测量结果。最后，有人认为光感受器细胞之间的缝隙连接可能通过抵消场电位的影响有效地使细胞的突触反应解耦。
