First published online April 18, 2008
Journal of Experimental Biology 211, 1376-1385 (2008)
Published by The Company of Biologists 2008
doi: 10.1242/jeb.015941
Retinal processing and opponent mechanisms mediating ultraviolet polarization sensitivity in rainbow trout (Oncorhynchus mykiss)
Samuel D. Ramsden1,
Leslie Anderson1,
Martina Mussi1,
Maarten Kamermans2,3 and
Craig W. Hawryshyn1,*
1 Department of Biology, University of Victoria, PO Box 3020 STN CSC, Victoria,
British Columbia, V8W 3N5, Canada
2 Retinal Signal Processing Group, Netherlands Institute for Neuroscience,
Meibergdreef 47, 1105 BA Amsterdam, The Netherlands
3 Department of Neurogenetics, Academic Medical Center, University of Amsterdam,
Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands

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Fig. 1. Spectral energy distribution of the adapting backgrounds. The irradiance
measurements are plotted as log irradiance (photons cm2
s–1). (A) Broad-spectrum tungsten halogen adapting background
used in control and cobalt PS and spectral sensitivity experiments. (B) UVS
cone mechanism, adapting background using a UG-11 filter in a tungsten halogen
background channel. (C) LWS cone mechanism, adapting background using a 600LP
cut-off filter.
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Fig. 2. Waveforms and response versus intensity curves for compound action
potential (CAP) and electroretinogram (ERG) recording. (A) CAP waveforms (`ON'
responses) at increasing intensities. Note that individual traces for A and B
were vertically displaced for clarity of presentation. Intensity was
incremented in 0.2 log unit steps of a 360 nm linearly polarized stimulus with
an e-vector orientation of 45°. (B) ERG waveforms at increasing
intensities recorded from a control fish (sham control, intraocular injection
of saline). (C) Response versus intensity curve based on CAP data
taken from panel A. (D) Response versus intensity curve based on ERG
data taken from B.
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Fig. 3. Mean normalized spectral sensitivity of rainbow trout (±1 standard
error) using electroretinogram (ERG) recording. For each treatment condition,
panels on the left side show the spectral sensitivity curves for the control
and treatment conditions and the panels on the right side show the difference
curves between the control and treatment spectral sensitivity. Green points
represent the control and red points represent the treatment condition. The
sensitivity measurements were normalized to 360 nm. (A) Mean normalized
spectral sensitivity of control fish where the spectral sensitivity was
measured using a broad-spectrum tungsten halogen background (N=3),
and treatment fish where spectral sensitivity was measured using a broad
spectrum and UG-11 background (N=3). (B) Mean difference spectrum as
a result of short wavelength chromatic adaptation (UG-11 filter). The black
line fitted to the data points at the shortwave end of the spectrum represents
an additive function based on the UVS and short wavelength-sensitive (SWS)
visual pigment templates. (C) Mean normalized spectral sensitivity of the same
control fish as in A, and treatment fish where spectral sensitivity was
measured using a broad spectrum and 600 nm long pass background
(N=3). (D) Mean difference spectrum as a result of long wavelength
chromatic adaptation (600 nm long pass filter). The black line fitted to the
points represents the LWS cone visual pigment template.
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Fig. 4. Mean ultraviolet polarization sensitivity of rainbow trout (±1
standard error). Two different recording techniques were used,
electroretinogram (ERG) and compound action potential (CAP) recording (solid
circles). Sv is represented by squares and
Sh by diamonds (see
Table 2 for weighting
coefficients). Dashed lines connect the symbols. (A) ERG PS (N=21).
The solid line connects the sensitivity points representing the intermediary
peaks. (B) CAP PS (N=5). For both figures, a 360 nm linear polarized
stimulus in 15° e-vector increments was used. Note the differences in
sensitivity between the two curves at 45° and 135°.
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Fig. 5. Mean ultraviolet polarization sensitivity of rainbow trout (±1
standard error). (A) Electroretinogram (ERG) UV PS with LWS cone mechanism
adaptation using the 600 nm long pass background (N=3). Note the
intermediary peak shifts towards the horizontal polarization mechanism and the
angular breadth of the horizontal polarization mechanism decreases while the
vertical polarization mechanism increases. (B) ERG UV PS with UVS cone
mechanism chromatic adaptation using a UG-11 background (N=3). Note
the intermediary peaks shift towards the vertical polarization mechanism and
the angular breadth of the horizontal polarization mechanism increases and the
vertical decreases. Sv is represented by squares and
Sh by diamonds. See
Table 2 for linear subtractive
model weighting functions.
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Fig. 6. Analysis of the effect of cobalt chloride on electroretinogram (ERG)
responses. (A) ERG waveforms at increasing intensities recorded from a
cobalt-treated fish (intraocular injection of cobalt chloride, intraocular
concentration of 0.275 mmol l–1). (B) Comparison of ERG
waveforms from cobalt chloride-injected fish (upper trace) and the control
(lower trace). (C) Response versus intensity based on ERG data taken
from a cobalt chloride-injected fish and a control fish. The cobalt-injected
fish show a lower slope in the dynamic range resulting in a difference in the
interpolated threshold intensity.
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Fig. 7. Mean normalized spectral sensitivity (±1 standard error). (A)
Sensitivity of control fish in green (N=3) and cobalt
chloride-treated fish (estimated intraocular concentration was 0.275 mmol
l–1; N=3) in red. (B) Mean difference spectrum
(control minus treated).
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Fig. 8. Mean normalized ultraviolet polarization sensitivity of rainbow trout
(±1 standard error). (A) Electroretinogram (ERG) UV PS of fish treated
with cobalt chloride (intraocular concentration 0.275 mmol
l–1; N=3). (B) Sham control intraocular injection of
saline (N=3). Sv is represented by squares and
Sh by diamonds. See
Table 2 for linear subtractive
model weighting factors.
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© The Company of Biologists Ltd 2008