Visual Adaptation in the Retina of the Skate

The electroretinogram (ERG) and single-unit ganglion cell activity were recorded from the eyecup of the skate (Raja erinacea and R. oscellata), and the adaptation properties of both types of response compared with in situ rhodopsin measurements obtained by fundus reflectometry. Under all conditions tested, the b-wave of the ERG and the ganglion cell discharge showed identical adaptation properties. For example, after flash adaptation that bleached 80% of the rhodopsin, neither ganglion cell nor b-wave activity could be elicited for 10–15 min. Following this unresponsive period, thresholds fell rapidly; by 20 min after the flash, sensitivity was within 3 log units of the dark-adapted level. Further recovery of threshold was slow, requiring an additional 70–90 min to reach absolute threshold. Measurements of rhodopsin levels showed a close correlation with the slow recovery of threshold that occurred between 20 and 120 min of dark adaptation; there is a linear relation between rhodopsin concentration and log threshold. Other experiments dealt with the initial unresponsive period induced by light adaptation. The duration of this unresponsive period depended on the brightness of the adapting field; with bright backgrounds, suppression of retinal activity lasted 20–25 min, but sensitivity subsequently returned and thresholds fell to a steady-state value. At all background levels tested, increment thresholds were linearly related to background luminance.

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Retinal mechanisms of visual adaptation in the skate.

The Journal of General Physiology ◽

10.1085/jgp.65.4.483 ◽

1975 ◽

Vol 65 (4) ◽

pp. 483-502 ◽

Cited By ~ 87

Author(s):

D G Green ◽

J E Dowling ◽

I M Siegel ◽

H Ripps

Keyword(s):

Ganglion Cell ◽

Cell Activity ◽

Receptor Potential ◽

Visual Adaptation ◽

Cell Discharge ◽

Cell Responses ◽

Electrical Potentials ◽

Rate Of Recovery ◽

Network Mechanism ◽

Different Levels

Electrical potentials were recorded from different levels within the skate retina. Comparing the adaptive properties of the various responses revealed that the isolated receptor potential and the S-potential always exhibited similar changes in sensitivity, and that the b-wave and ganglion-cell thresholds acted in concert. However, the two sets of responses behaved differently under certain conditions. For example, a dimly iluminated background that had no measurable effect on the senitivities of either of the distal responses, raised significantly the thresholds of both the b-wave and the ganglion cell responses. In addition, the rate of recovery during the early, "neural" phase of dark adaptation was significantly faster for the receptor and S-potentials than for the b-wave or ganglion cell discharge. These results indicate that there is an adaptive ("network") mechanism in the retina which can influence significantly b-wave and gaglion cell activity and which behaves independently of the receptors and horizontal cells. We conclude that visual adaptation in the skate retina is regulated by a combination of receptoral and network mechanisms.

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In Situ Monitoring of Polaron Localization and Cell Activity with Charge Accumulation Spectroscopy

Advanced Functional Materials ◽

10.1002/adfm.202105799 ◽

2021 ◽

pp. 2105799

Author(s):

Yu Zhang ◽

Li Yang ◽

Jintao Wang ◽

Wangying Xu ◽

Qiming Zeng ◽

...

Keyword(s):

Cell Activity ◽

In Situ Monitoring ◽

Charge Accumulation

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Physiological effects of muscarinic vs nicotinic ACh antagonists upon ganglion cell activity in the frog retina

Vision Research ◽

10.1016/0042-6989(87)90120-9 ◽

1987 ◽

Vol 27 (12) ◽

pp. 2061-2072 ◽

Cited By ~ 8

Author(s):

N. Bonaventure ◽

B. Jardon ◽

N. Wioland ◽

G. Rudolf

Keyword(s):

Ganglion Cell ◽

Cell Activity ◽

Physiological Effects ◽

Frog Retina

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Relation between Ganglion Cell Activity and the Local Electroretinogram of Cat Retina

Nature ◽

10.1038/2161008a0 ◽

1967 ◽

Vol 216 (5119) ◽

pp. 1008-1010 ◽

Cited By ~ 4

Author(s):

ROY H. STEINBERG

Keyword(s):

Ganglion Cell ◽

Cell Activity ◽

Cat Retina

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Visualization is crucial for understanding microbial processes in the ocean

Philosophical Transactions of the Royal Society B Biological Sciences ◽

10.1098/rstb.2019.0083 ◽

2019 ◽

Vol 374 (1786) ◽

pp. 20190083 ◽

Cited By ~ 5

Author(s):

Marta Sebastián ◽

Josep M. Gasol

Keyword(s):

Single Cell ◽

Metabolic Activity ◽

Cell Activity ◽

Level Of Activity ◽

Single Cell Activity ◽

Recent Developments ◽

Insight Into ◽

Do So

Recent developments in community and single-cell genomic approaches have provided an unprecedented amount of information on the ecology of microbes in the aquatic environment. However, linkages between each specific microbe's identity and their in situ level of activity (be it growth, division or just metabolic activity) are much more scarce. The ultimate goal of marine microbial ecology is to understand how the environment determines the types of different microbes in nature, their function, morphology and cell-to-cell interactions and to do so we should gather three levels of information, the genomic (including identity), the functional (activity or growth), and the morphological, and for as many individual cells as possible. We present a brief overview of methodologies applied to address single-cell activity in marine prokaryotes, together with a discussion of the difficulties in identifying and categorizing activity and growth. We then provide and discuss some examples showing how visualization has been pivotal for challenging established paradigms and for understanding the role of microbes in the environment, unveiling processes and interactions that otherwise would have been overlooked. We conclude by stating that more effort should be directed towards integrating visualization in future approaches if we want to gain a comprehensive insight into how microbes contribute to the functioning of ecosystems. This article is part of a discussion meeting issue ‘Single cell ecology’.

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