Retinotopic organization of lateral eye input to Limulus brain

1982 ◽  
Vol 48 (2) ◽  
pp. 505-520 ◽  
Author(s):  
S. C. Chamberlain ◽  
R. B. Barlow
Keyword(s):  
Optic Nerve ◽  
Subunit Structure ◽  
Combined Effects ◽  
Microelectrode Recordings ◽  
Basic Subunit ◽  
Lateral Eye ◽  
Retinotopic Organization ◽  
The Brain ◽  
Simple Rotation ◽  
Anterior Posterior

1. The retinotopic organization of retinal inputs from the lateral eye of Limulus to the optic ganglia of the brain was determined from microelectrode recordings of nerve impulses. 2. The central connections of the natural subunits of the lateral optic nerve were determined using cobalt impregnation of cut axons. 3. Complete retinal maps exist in both the lamina and medulla. The laminar map is a simple rotation and folding of the retinal array. The medullar map is more complex as a result of the combined effects of the chiasma and the basic subunit structure of the optic nerve, which is preserved in the lamina and medulla. 4. The chiasma between the lamina and medulla reverses the anterior-posterior axis of the retinal map. There is no corresponding reversal in the dorsal-ventral axis.

scholarly journals Efferent control of temporal response properties of the Limulus lateral eye.

1990 ◽  
Vol 95 (2) ◽  
pp. 229-244 ◽  
Author(s):  
R Batra ◽  
R B Barlow
Keyword(s):  
Optic Nerve ◽  
Low Frequency ◽  
Transfer Characteristic ◽  
Nerve Fibers ◽  
Visual Sensitivity ◽  
Temporal Response ◽  
Lateral Eye ◽  
Rapid Changes ◽  
Modulated Light ◽  
The Brain

The sensitivity of the Limulus lateral eye exhibits a pronounced circadian rhythm. At night a circadian oscillator in the brain activates efferent fibers in the optic nerve, inducing multiple changes in the physiological and anatomical characteristics of retinal cells. These changes increase the sensitivity of the retina by about five orders of magnitude. We investigated whether this increase in retinal sensitivity is accompanied by changes in the ability of the retina to process temporal information. We measured the frequency transfer characteristic (FTC) of single receptors (ommatidia) by recording the response of their optic nerve fibers to sinusoidally modulated light. We first measured the FTC in the less sensitive daytime state and then after converting the retina to the more sensitive nighttime state by electrical stimulation of the efferent fibers. The activation of these fibers shifted the peak of the FTC to lower frequencies and reduced the slope of the low-frequency limb. These changes reduce the eye's ability to detect rapid changes in light intensity but enhance its ability to detect dim flashes of light. Apparently Limulus sacrifices temporal resolution for increased visual sensitivity at night.

Histochemical localization of acetylcholinesterase in the lateral eye and brain of Limulus polyphemus: Might acetylcholine be a neurotransmitter for lateral inhibition in the lateral eye?

1994 ◽  
Vol 11 (5) ◽  
pp. 989-1001 ◽  
Author(s):  
Eric P. Hornstein ◽  
Daniel L. Sambursky ◽  
Steven C. Chamberlain
Keyword(s):  
Optic Nerve ◽  
Lateral Inhibition ◽  
Horseshoe Crab ◽  
Compound Eye ◽  
Nerve Fibers ◽  
Intense Staining ◽  
Histaminergic Neurons ◽  
Lateral Eye ◽  
Weak Staining ◽  
The Brain

AbstractThe distribution of acetylcholinesterase (AChE) in the lateral eye and brain of the horseshoe crab was investigated with histochemical means using standard controls to eliminate butyrylcholinesterase and nonspecific staining. Intense staining was observed in the neural plexus of the lateral compound eye, in the lateral optic nerve, and in various neuropils of the brain. Nerve fibers with moderate to weak staining were widespread in the brain. No sornata were stained in either the lateral eye or the brain. The distribution of acetylcholinesterase in the supraesophageal ganglia and nerves of the giant barnacle was also investigated for comparison. Although both the median optic nerve of the barnacle and the lateral optic nerve of the horseshoe crab appear to contain the fibers of histaminergic neurons, only the lateral optic nerve of the horseshoe crab shows AChE staining. Other parts of the barnacle nervous system, however, showed intense AChE staining. These results along with the histochemical controls eliminate the possibility that some molecule found in histaminergic neurons accounted for the AChE staining but support the possibility that acetylcholine might be involved as a neurotransmitter in lateral inhibition in the horseshoe crab retina. Two reasonable neurotransmitter candidates for lateral inhibition, histamine and acetylcholine, must now be investigated.

Neurotransmitter systems of female mouse brain during growth of malignant melanoma modeled on the background of chronic pain

2018 ◽  
pp. 49-55
Author(s):  
О.И. Кит ◽  
И.М. Котиева ◽  
Е.М. Франциянц ◽  
И.В. Каплиева ◽  
Л.К. Трепитаки ◽  
...  
Keyword(s):  
Chronic Pain ◽  
Cerebral Cortex ◽  
Malignant Melanoma ◽  
Sciatic Nerve ◽  
Female Mouse ◽  
Combined Effects ◽  
Malignant Growth ◽  
Course Of Disease ◽  
The Brain ◽  
Melanoma Growth

Известно, что биогенные амины (БА) участвуют в злокачественном росте, их уровень изменяется в ЦНС при болевом воздействии, однако исследований о сочетанном влиянии хронической боли (ХБ) и онкопатологии на динамику БА в головном мозге не проводилось. Цель: изучить особенности баланса БА в коре головного мозга в динамике роста меланомы, воспроизведенной на фоне ХБ. Материалы и методы. Работа выполнена на 64 мышах-самках, весом 21-22 г. Животным основной группы меланому В16/F10 перевивали под кожу спины через 2 недели после перевязки седалищных нервов. Группой сравнения служили мыши с меланомой без боли. Уровни БА: адреналина, норадреналина, дофамина (ДА), серотонина (5-НТ), гистамина, а также 5-ОИУК определяли методом иммуноферментного анализа. Результаты. У мышей с ХБ уменьшается содержание большинства БА, однако уровень ДА не изменяется. Метаболизм 5-НТ происходит с участием МАО. Развитие меланомы сопровождается увеличением содержания ДА и 5-НТ, тогда как МАО - ингибируется. Направленность сдвигов БА при развитии меланомы на фоне ХБ оказалась практически такой же, как и без неё. В то же время ХБ ограничивает накопление 5-НТ в коре мозга при меланоме, что сопровождается более агрессивным её течением. Выводы. ХБ ограничивает включение стресс-лимитирующих механизмов в головном мозге при развитии меланомы у мышей, что приводит к более агрессивному течению злокачественного процесса. Biogenic amines (BA) are known to be involved in malignant growth, and their CNS levels change in pain; however, there are no studies of combined effects of chronic pain (CP) and cancer on BA dynamics in the brain. Aim: To study features of BA balance in the cerebral cortex during melanoma growth associated with CP. Material and methods. The study included 64 female mice weighing 21-22 g. In the main groups, B16/F10 melanoma was transplanted under the skin of the back two weeks following sciatic nerve ligation. Mice with melanoma without pain were used as the control. Concentrations of BA: adrenaline, noradrenaline, dopamine (DA), serotonin (5-HT), histamine and 5-HIAA were measured with ELISA. Results. Concentrations of BAs decreased in mice with CP although DA levels did not change. 5-HT metabolism involved MAO. The development of melanoma was accompanied by increases in DA and 5-HT whereas MAO was inhibited. The direction of BA changes during the development of melanoma was the same with and without CP. At the same time, CP with melanoma limited accumulation of 5-HT in the cerebral cortex, which resulted in even more aggressive course of cancer. Conclusion. CP restricted the activation of cerebral stress-limiting mechanisms during the development of melanoma in mice, which resulted in a more aggressive course of disease.

scholarly journals Endocrine Dysfunction in Children with Zika-Related Microcephaly Who Were Born during the 2015 Epidemic in the State of Pernambuco, Brazil

Viruses ◽  
2020 ◽  
Vol 13 (1) ◽  
pp. 1
Author(s):  
Andréia Veras Gonçalves ◽  
Demócrito de B. Miranda-Filho ◽  
Líbia Cristina Rocha Vilela ◽  
Regina Coeli Ferreira Ramos ◽  
Thalia V. B. de Araújo ◽  
...  
Keyword(s):  
Optic Nerve ◽  
Viral Infections ◽  
Case Series ◽  
Optic Nerve Hypoplasia ◽  
Endocrine Dysfunction ◽  
Careful Monitoring ◽  
Early Puberty ◽  
Growth Impairment ◽  
Appropriate Treatment ◽  
The Brain

Congenital viral infections and the occurrence of septo-optic dysplasia, which is a combination of optic nerve hypoplasia, abnormal formation of structures along the midline of the brain, and pituitary hypofunction, support the biological plausibility of endocrine dysfunction in Zika-related microcephaly. In this case series we ascertained the presence and describe endocrine dysfunction in 30 children with severe Zika-related microcephaly from the MERG Pediatric Cohort, referred for endocrinological evaluation between February and August 2019. Of the 30 children, 97% had severe microcephaly. The average age at the endocrinological consultation was 41 months and 53% were female. The most frequently observed endocrine dysfunctions comprised short stature, hypothyroidism, obesity and variants early puberty. These dysfunctions occurred alone 57% or in combination 43%. We found optic nerve hypoplasia (6/21) and corpus callosum hypoplasia (20/21). Seizure crises were reported in 86% of the children. The most common—and clinically important—endocrine dysfunctions were pubertal dysfunctions, thyroid disease, growth impairment, and obesity. These dysfunctions require careful monitoring and signal the need for endocrinological evaluation in children with Zika-related microcephaly, in order to make early diagnoses and implement appropriate treatment when necessary.

scholarly journals Photoreceptive retinal ganglion cells control the information rate of the optic nerve

2018 ◽  
Vol 115 (50) ◽  
pp. E11817-E11826 ◽  
Author(s):  
Nina Milosavljevic ◽  
Riccardo Storchi ◽  
Cyril G. Eleftheriou ◽  
Andrea Colins ◽  
Rasmus S. Petersen ◽  
...  
Keyword(s):  
Optic Nerve ◽  
Retinal Ganglion Cells ◽  
Information Flow ◽  
Information Transfer ◽  
Ganglion Cells ◽  
Retinal Ganglion ◽  
Ambient Light ◽  
Visual Responses ◽  
Light Irradiance ◽  
The Brain

Information transfer in the brain relies upon energetically expensive spiking activity of neurons. Rates of information flow should therefore be carefully optimized, but mechanisms to control this parameter are poorly understood. We address this deficit in the visual system, where ambient light (irradiance) is predictive of the amount of information reaching the eye and ask whether a neural measure of irradiance can therefore be used to proactively control information flow along the optic nerve. We first show that firing rates for the retina’s output neurons [retinal ganglion cells (RGCs)] scale with irradiance and are positively correlated with rates of information and the gain of visual responses. Irradiance modulates firing in the absence of any other visual signal confirming that this is a genuine response to changing ambient light. Irradiance-driven changes in firing are observed across the population of RGCs (including in both ON and OFF units) but are disrupted in mice lacking melanopsin [the photopigment of irradiance-coding intrinsically photosensitive RGCs (ipRGCs)] and can be induced under steady light exposure by chemogenetic activation of ipRGCs. Artificially elevating firing by chemogenetic excitation of ipRGCs is sufficient to increase information flow by increasing the gain of visual responses, indicating that enhanced firing is a cause of increased information transfer at higher irradiance. Our results establish a retinal circuitry driving changes in RGC firing as an active response to alterations in ambient light to adjust the amount of visual information transmitted to the brain.

scholarly journals Ocular, Neurologic and Systemic Findings of the Cases with Optic Nerve Hypoplasia

2016 ◽  
Vol 10 (1) ◽  
pp. 5-11 ◽  
Author(s):  
Eyyup Karahan ◽  
Ayse Tulin Berk
Keyword(s):  
Optic Nerve ◽  
Chart Review ◽  
Retrospective Chart Review ◽  
Optic Nerve Hypoplasia ◽  
Refractive Errors ◽  
Poor Vision ◽  
The Relationship ◽  
The Brain ◽  
Ocular Signs ◽  
Neurologic Findings

Aim: To describe the associated ocular, neurologic, and systemic findings in a population of children with optic nerve hypoplasia (ONH) and to evaluate the relationship between ocular signs and neurologic findings. Method: A retrospective chart review of 53 patients with the diagnosis of ONH seen between December 1998 and September 2012 was performed. All neurodevelopmental anomalies, neuroradiologic findings, endocrinologic and systemic findings were recorded. Poor vision was defined as the visual acuity poorer than logMAR 1.0 or inadequate central steady maintained fixation. Results: Thirty (56.6%) of the 53 children with ONH were boys. Mean age at presentation was 56.2±46.8 months (range; 3 months to 18 years). Poor vision defined for the purpose of this study was found in 47.2% of 53 patients. Thirty-three (62.3%) children had nystagmus. Thirty-four (64.2%) children had strabismus. Thirteen (38.2%) of those with strabismus had esotropia, 20 (58.8%) had exotropia. The total number of the children with neurodevelopmental deficit was 22 (41.5%) in our study. Conclusion: The vision of young children with ONH should be monitored at least annually, and any refractive errors should be treated. Neuroimaging of the brain and endocrinologic evaluation is necessary in all cases with ONH.

A developmental and ultrastructural study of the optic chiasma in Xenopus

Development ◽  
1988 ◽  
Vol 102 (3) ◽  
pp. 537-553
Author(s):  
M.A. Wilson ◽  
J.S. Taylor ◽  
R.M. Gaze
Keyword(s):  
Optic Nerve ◽  
Cell Mass ◽  
Light And Electron Microscopy ◽  
Optic Tract ◽  
Retinal Ganglion ◽  
Intercellular Spaces ◽  
Optic Chiasma ◽  
Cell Processes ◽  
Optic Axons ◽  
The Brain

The structure of the optic chiasma in Xenopus tadpoles has been investigated by light and electron microscopy. Where the optic nerve approaches the chiasma, a tongue of cells protrudes from the periventricular cell mass into the dorsal part of the nerve. Glial processes from this tongue of cells ensheath fascicles of optic axons as they enter the brain. Coincident with this partitioning, the annular arrangement of axons in the optic nerve changes to the laminar organization of the optic tract. Beyond the site of this rearrangement, all newly growing axons accumulate in the ventral-most part of the nerve and pass into the region between the periventricular cells and pia which we have called the ‘bridge’. This region is characterized by a loose meshwork of glial cell processes, intercellular spaces and the presence of both optic and nonoptic axons. In the bridge, putative growth cones of retinal ganglion cell axons are found in the intercellular spaces in contact with both the glia and with other axons. The newly growing axons from each eye cross in the bridge at the midline and pass into the superficial layers of the contralateral optic tracts. As the system continues to grow, previous generations of axon, which initially crossed in the existing bridge, are displaced dorsally and caudally, forming the deeper layers of the chiasma. At their point of crossing in the deeper layers, these fascicles of axons from each eye interweave in an intimate fashion. There is no glial segregation of the older axons as they interweave within the chiasma.

Visual recovery following optic nerve crush in male and female wild-type and TRIF-deficient mice

2020 ◽  
Vol 38 (5) ◽  
pp. 355-368
Author(s):  
Yimeng Lina Du ◽  
Elena G. Sergeeva ◽  
Donald G. Stein
Keyword(s):  
Optic Nerve ◽  
Inflammatory Response ◽  
Functional Recovery ◽  
Inflammatory Responses ◽  
Optic Nerve Crush ◽  
Optomotor Response ◽  
Nerve Crush ◽  
Inflammatory Damage ◽  
Visual Cortices ◽  
The Brain

Background: There is growing evidence that the TIR-domain-containing adapter-inducing interferon-β (TRIF) pathway is implicated in the modulation of neuroinflammation following injuries to the brain and retina. After exposure to injury or to excitotoxic pathogens, toll-like receptors (TLR) activate the innate immune system signaling cascade and stimulate the release of inflammatory cytokines. Inhibition of the TLR4 receptor has been shown to enhance retinal ganglion cell (RGC) survival in optic nerve crush (ONC) and in ischemic injury to other parts of the brain. Objective: Based on this evidence, we tested the hypothesis that mice with the TRIF gene knocked out (TKO) will demonstrate decreased inflammatory responses and greater functional recovery after ONC. Methods: Four experimental groups –TKO ONC (12 males and 8 females), WT ONC (10 males and 8 females), TKO sham (9 males and 5 females), and WT sham (7 males and 5 females) –were used as subjects. Visual evoked potentials (VEP) were recorded in the left and right primary visual cortices and optomotor response were assessed in all mice at 14, 30, and 80 days after ONC. GFAP and Iba-1 were used as markers for astrocytes and microglial cells respectively at 7 days after ONC, along with NF-kB to measure inflammatory effects downstream of TRIF activation; RMPBS marker was used to visualize RGC survival and GAP-43 was used as a marker of regenerating optic nerve axons at 30 days after ONC. Results: We found reduced inflammatory response in the retina at 7 days post-ONC, less RGC loss and greater axonal regeneration 30 days post-ONC, and better recovery of visual function 80 days post-ONC in TKO mice compared to WT mice. Conclusions: Our study showed that the TRIF pathway is involved in post-ONC inflammatory response and gliosis and that deletion of TRIF induces better RGC survival and regeneration and better functional recovery in mice. Our results suggest the TRIF pathway as a potential therapeutic target for reducing the inflammatory damage caused by nervous system injury.

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