dc.contributor.author |
Van der Merwe, Ingrid
|
|
dc.contributor.author |
Lukats, Akos
|
|
dc.contributor.author |
Blahova, Veronika
|
|
dc.contributor.author |
Oosthuizen, Maria Kathleen
|
|
dc.contributor.author |
Bennett, Nigel Charles
|
|
dc.contributor.author |
Nemec, Pavel
|
|
dc.date.accessioned |
2018-10-18T05:59:27Z |
|
dc.date.available |
2018-10-18T05:59:27Z |
|
dc.date.issued |
2018-08-09 |
|
dc.description.abstract |
We used immunocytochemistry to determine the presence and topographical density distributions
of rods, cones, and intrinsically photosensitive retinal ganglion cells (ipRGCs) in the
four-striped field mouse (Rhabdomys pumilio) and the Namaqua rock mouse (Micaelamys
namaquensis). Both species possessed duplex retinas that were rod dominated. In R. pumilio,
the density of both cones and rods were high (cone to rod ratio: 1:1.23) and reflected the
species' fundamentally diurnal, but largely crepuscular lifestyle. Similarly, the ratio of cones
to rods in M. namaquensis (1:12.4) reflected its nocturnal lifestyle. Similar rod density peaks
were observed (R. pumilio: ~84467/mm2; M. namaquensis: ~81088/mm2), but a density gradient
yielded higher values in the central (~56618/mm2) rather than in the peripheral retinal
region (~32689/mm2) in R. pumilio. Two separate cone types (S-cones and M/L-cones)
were identified implying dichromatic color vision in the study species. In M. namaquensis,
both cone populations showed a centro-peripheral density gradient and a consistent S- to
M/L-cone ratio (~1:7.8). In R. pumilio, S cones showed a centro-peripheral gradient (S- to
M/L-cone ratio; central: 1:7.8; peripheral: 1:6.8) which appeared to form a visual streak, and
a specialized area of M/L-cones (S- to M/L-cone ratio: 1:15) was observed inferior to the
optic nerve. The number of photoreceptors per linear degree of visual angle, estimated from
peak photoreceptor densities and eye size, were four cones and 15 rods per degree in M.
namaquensis and 11 cones and 12 rods per degree in R. pumilio. Thus, in nocturnal M.
namaquensis rods provide much finer image sampling than cones, whereas in diurnal/crepuscular
R. pumilio both photoreceptor types provide fine image sampling. IpRGCs were comparably sparse in R. pumilio (total = 1012) and M. namaquensis (total = 862), but were
homogeneously distributed in M. namaquensis and densest in the dorso-nasal quadrant in
R. pumilio. The adaptive significance of the latter needs further investigation. |
en_ZA |
dc.description.department |
Mammal Research Institute |
en_ZA |
dc.description.department |
Zoology and Entomology |
en_ZA |
dc.description.librarian |
am2018 |
en_ZA |
dc.description.sponsorship |
The Grant Agency of Charles University
(325515, to VB) and the DST-NRF SARChI chair of Mammal Behavioural Ecology and
Physiology (64756, to NCB). Microscopy was performed in the Laboratory of Confocal and Fluorescence
Microscopy co-financed by the European Regional Development Fund and the state
budget of the Czech Republic (CZ.1.05/4.1.00/16.0347 and CZ.2.16/3.1.00/21515). |
en_ZA |
dc.description.uri |
http://www.plosone.org |
en_ZA |
dc.identifier.citation |
Van der Merwe I, Lukáts Á, Bláhová V, Oosthuizen MK, Bennett NC, Němec P (2018) The topography of rods, cones and intrinsically photosensitive retinal ganglion cells in the retinas of a nocturnal (Micaelamys namaquensis) and a diurnal (Rhabdomys pumilio) rodent. PLoS ONE 13(8): e0202106. https://doi.org/10.1371/journal.pone.0202106. |
en_ZA |
dc.identifier.issn |
1932-6203 (online) |
|
dc.identifier.other |
10.1371/journal.pone.0202106 |
|
dc.identifier.uri |
http://hdl.handle.net/2263/66937 |
|
dc.language.iso |
en |
en_ZA |
dc.publisher |
Public Library of Science |
en_ZA |
dc.rights |
© 2018 van der Merwe et al. This is an open access article distributed under the terms of the Creative Commons Attribution License. |
en_ZA |
dc.subject |
Rodent |
en_ZA |
dc.subject |
Immunocytochemistry |
en_ZA |
dc.subject |
Density |
en_ZA |
dc.subject |
Photoreceptors |
en_ZA |
dc.subject |
Mouse retina |
en_ZA |
dc.subject |
Architecture |
en_ZA |
dc.subject |
Photoentrainment |
en_ZA |
dc.subject |
Eye |
en_ZA |
dc.subject |
Vision |
en_ZA |
dc.subject |
Light |
en_ZA |
dc.subject |
Rats |
en_ZA |
dc.subject |
Mammalian retina |
en_ZA |
dc.subject |
Locomotor activity |
en_ZA |
dc.subject |
Ocular photoreceptors |
en_ZA |
dc.subject |
Intrinsically photosensitive retinal ganglion cells (ipRGCs) |
en_ZA |
dc.title |
The topography of rods, cones and intrinsically photosensitive retinal ganglion cells in the retinas of a nocturnal (Micaelamys namaquensis) and a diurnal (Rhabdomys pumilio) rodent |
en_ZA |
dc.type |
Article |
en_ZA |