Direction-selective retinal ganglion cells and control of optokinetic nystagmus in the rabbit

Migraineurs avoid light because it intensifies their headache. However, this is not the only reason for their aversion to light. Studying migraineurs and control subjects, we found that lights triggered more changes in autonomic functions and negative emotions during, rather than in the absence of, migraine or in control subjects, and that the association between light and positive emotions was stronger in control subjects than migraineurs. Seeking to define a neuroanatomical substrate for these findings, we showed that, in rats, axons of retinal ganglion cells converge on hypothalamic neurons that project directly to nuclei in the brainstem and spinal cord that regulate parasympathetic and sympathetic functions and contain dopamine, histamine, orexin, melanin-concentrating hormone, oxytocin, and vasopressin. Although the rat studies define frameworks for conceptualizing how light triggers the symptoms described by patients, the human studies suggest that the aversive nature of light is more complex than its association with headache intensification.

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Analysis of vertebrate eye movements following intravitreal drug injections. I. Blockade of retinal ON-cells by 2-amino-4-phosphonobutyrate eliminates optokinetic nystagmus

Journal of Neurophysiology ◽

10.1152/jn.1988.60.3.1010 ◽

1988 ◽

Vol 60 (3) ◽

pp. 1010-1021 ◽

Cited By ~ 16

Author(s):

A. G. Knapp ◽

M. Ariel ◽

F. R. Robinson

Keyword(s):

Visual Cortex ◽

Eye Movements ◽

Retinal Ganglion Cells ◽

Optokinetic Nystagmus ◽

Ganglion Cells ◽

Directional Asymmetry ◽

Retinal Ganglion ◽

Binocular Stimulation ◽

Vertebrate Eye ◽

Stimulation Of

1. Horizontal optokinetic nystagmus (OKN) was examined in alert rabbits and cats following intravitreal injection of 2-amino-4-phosphonobutyrate (APB), an agent which selectively blocks the light-responsiveness of retinal ON-cells while having little effect on OFF-cells. The retinal actions of APB were assessed independently by electroretinography. 2. In five rabbits, doses of APB sufficient to eliminate the b-wave of the electroretinogram reduced drastically the ability of the injected eye to drive OKN at all stimulus speeds tested (1-96 degrees/s). Impairment of OKN was apparent within minutes of the injection, remained maximal for several hours, and recovered completely in 1-7 days. OKN in response to stimulation of the uninjected eye alone remained qualitatively and quantitatively normal. 3. Following administration of APB, OKN in response to binocular stimulation displayed a directional asymmetry. Stimuli moving in the preferred (temporal-to-nasal) direction for the uninjected eye became more effective than stimuli moving in the opposite direction, indicating that the injected eye could no longer contribute to binocular OKN. 4. When rabbits viewed stationary stimuli through the APB-treated eye alone, episodes of slow (less than 1 degrees/s) ocular drift were observed, similar to the positional instability seen when rabbits are placed in darkness or when the retinal image is stablized artifically (12). 5. APB had little effect on OKN in normal cats. In two cats that had previously received large lesions of the visual cortex, however, APB eliminated the ability of the injected eye to drive monocular OKN. The extent of the impairment was similar to that seen in rabbits. Because the cortex is thought to contribute more to OKN in cats than in rabbits, this result suggests that the optokinetic pathways disrupted by APB project subcortically. 6. This study demonstrates that the integrity of retinal ON-cells is required to sustain normal OKN. The results are consistent with additional anatomic and physiological evidence suggesting that a particular subclass of retinal ganglion cells, the ON-direction-selective cells, may provide a crucial source of visual input to central optokinetic pathways.

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Retinal Ganglion Cells Related to Optokinetic Nystagmus in Mammals.

Equilibrium Research ◽

10.3757/jser.55.251 ◽

1996 ◽

Vol 55 (3) ◽

pp. 251-261

Author(s):

Tomoyuki Okada

Keyword(s):

Retinal Ganglion Cells ◽

Optokinetic Nystagmus ◽

Ganglion Cells ◽

Retinal Ganglion

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Destructive Effect of Intravitreal Heat Shock Protein 27 Application on Retinal Ganglion Cells and Neurofilament

International Journal of Molecular Sciences ◽

10.3390/ijms21020549 ◽

2020 ◽

Vol 21 (2) ◽

pp. 549 ◽

Cited By ~ 2

Author(s):

Pia Grotegut ◽

Sandra Kuehn ◽

H. Burkhard Dick ◽

Stephanie C. Joachim

Keyword(s):

Heat Shock ◽

Heat Shock Protein ◽

Retinal Ganglion Cells ◽

Ganglion Cells ◽

Amacrine Cells ◽

Heat Shock Protein 27 ◽

Bipolar Cells ◽

Retinal Ganglion ◽

Destructive Effect ◽

And Control

Heat shock protein 27 (HSP27) is commonly involved in cellular stress. Increased levels of HSP27 as well as autoantibodies against this protein were previously detected in glaucoma patients. Moreover, systemic immunization with HSP27 induced glaucoma-like damage in rodents. Now, for the first time, the direct effects of an intravitreal HSP27 application were investigated. For this reason, HSP27 or phosphate buffered saline (PBS, controls) was applied intravitreally in rats (n = 12/group). The intraocular pressure (IOP) as well as the electroretinogram recordings were comparable in HSP27 and control eyes 21 days after the injection. However, significantly fewer retinal ganglion cells (RGCs) and amacrine cells were observed in the HSP27 group via immunohistochemistry and western blot analysis. The number of bipolar cells, on the other hand, was similar in both groups. Interestingly, a stronger neurofilament degeneration was observed in HSP27 optic nerves, while no differences were noted regarding the myelination state. In summary, intravitreal HSP27 injection led to an IOP-independent glaucoma-like damage. A degeneration of RGCs as well as their axons and amacrine cells was noted. This suggests that high levels of extracellular HSP27 could have a direct damaging effect on RGCs.

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