Fite K V, Wang S R
Brain Behav Evol. 1986;28(4):198-206. doi: 10.1159/000118703.
Microiontophoresis of acetylcholine (ACh), atropine, or curare was accompanied by single-unit analysis of visual neuronal responses in the optic tectum of Rana nigromaculata. In 71% of the units tested, ACh enhanced responses to visual stimuli, while atropine suppressed visual responses. Twenty-two percent of the remainder showed no ACh- or atrophin-induced effects and were recorded within 125 microns of the pial surface. The majority of ACh-enhanced, atropine-suppressed units were recorded from visually responsive units localized in the postsynaptic cellular layer 8. The iontophoretic effects of curare were considerably more varied, with approximately equal numbers of units showing an increase (33%), a decrease (35%) or no change (32%) in visually activated responses. The specific effects of curare were also related to the depth from which unit recordings were obtained. These findings indicate that ACh functions as a modulatory neurotransmitter in the frog optic tectum, with a predominantly muscarinic mode of action at postsynaptic levels.
对黑斑蛙视顶盖的视觉神经元反应进行单单位分析的同时，对乙酰胆碱（ACh）、阿托品或箭毒进行了微离子透入。在71%的受试单位中，ACh增强了对视觉刺激的反应，而阿托品则抑制了视觉反应。其余22%的单位未表现出ACh或阿托品诱导的效应，这些单位是在软脑膜表面125微米范围内记录的。大多数ACh增强、阿托品抑制的单位是从位于突触后细胞层8的视觉反应单位记录的。箭毒的离子透入效应变化更大，大约相同数量的单位在视觉激活反应中表现出增加（33%）、减少（35%）或无变化（32%）。箭毒的特定效应也与获得单位记录的深度有关。这些发现表明，ACh在蛙视顶盖中作为一种调节性神经递质发挥作用，在突触后水平主要以毒蕈碱作用模式起作用。
