Categorical and Prolonged Potentials Are Evoked when Brief, Intermediate-Intensity Flashes Stimulate Horseshoe Crab Lateral Eye Photoreceptors during Octopamine Neuromodulation
| العنوان: | Categorical and Prolonged Potentials Are Evoked when Brief, Intermediate-Intensity Flashes Stimulate Horseshoe Crab Lateral Eye Photoreceptors during Octopamine Neuromodulation |
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| المؤلفون: | Gerald S. Wasserman, Corrinne C.M. Lim |
| المصدر: | Neurosignals. 10:399-415 |
| بيانات النشر: | S. Karger AG, 2001. |
| سنة النشر: | 2001 |
| مصطلحات موضوعية: | animal structures, Light, genetic structures, Efferent, Receptor potential, In Vitro Techniques, Models, Biological, Cellular and Molecular Neuroscience, chemistry.chemical_compound, Developmental Neuroscience, Horseshoe Crabs, Animals, Neurotransmitter, Octopamine, Neurotransmitter Agents, biology, Octopamine (drug), biology.organism_classification, eye diseases, Neuromodulation (medicine), Horseshoe crab, Electrophysiology, Neurology, chemistry, Limulus, Evoked Potentials, Visual, Photoreceptor Cells, Invertebrate, sense organs, Neuroscience, Signal Transduction |
| الوصف: | Octopamine, a major efferent neurotransmitter in the lateral eye of the horseshoe crab (Limulus polyphemus), has previously been shown to modulate photoreceptor responses evoked by long flashes. Quantification of these data indicates that this modulation produced a genuine increase in sensitivity to light which cannot be entirely due to an increase in optical efficiency consequent on an anatomical alteration. Other previous studies demonstrated that extrinsic current can modulate Limulus lateral eye photoreceptor cells by inducing a bistable membrane potential with two distinct states. The present study was therefore undertaken to find out if octopamine could modulate visual responses by inducing prolonged and bistable polarization shifts similar to those demonstrated in several other neural systems. Intracellular microelectrodes were used to execute an electrophysiological study of the receptor potentials evoked in the lateral eye of Limulus when brief (20-ms) flashes were delivered while 50 microM octopamine perfused dark-adapted photoreceptors. The combined chemical and optical stimuli prolonged photoreceptor responses to light to the degree that they often exceeded the duration of the brief stimulus by hundreds of milliseconds. Moreover, these prolonged potentials were clearly bistable because they were categorical--either a prolongation was perceptually clear-cut and present or it was not, with no intermediate patterns being observed. During seawater control perfusions, such prolongations were absent. This appears to be the first demonstration of such categorical and prolonged potentials in a photoreceptor neuron. This finding particularly suggests that efferent-driven neuromodulation can enable the development of a persisting short-term representation of a brief stimulus, with this representation being retained at the most distal possible neural site. |
| تدمد: | 1424-8638 1424-862X |
| الوصول الحر: | https://explore.openaire.eu/search/publication?articleId=doi_dedup___::34c346774afd947b08e225e951dc461eTest https://doi.org/10.1159/000046907Test |
| حقوق: | OPEN |
| رقم الانضمام: | edsair.doi.dedup.....34c346774afd947b08e225e951dc461e |
| قاعدة البيانات: | OpenAIRE |
| تدمد: | 14248638 1424862X |
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