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Effects of pattern deprivation on the development of the motion-sensitive posterior medial lateral suprasylvian (PMLS) visual area of the cat as revealed by zif268 gene expression

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Zapasnik M., Laskowska-Macios K., Hu T. T., Kossut M., Arckens L., Burnat K.

Acta Neurobiologiae Experimentalis

2011

tom 71

nr S

Long-term binocular pattern deprivation (BD) from eye opening results in severe global motion perception impairment in children and cats. We recently showed in cat that late onset deprivation (month 3 and 4 following 2 months of normal vision; 2N2BD), also leads to global motion perception impairments. Interestingly, 2 months of BD from eye opening facilitates motion perception, while a continuous 4 month BD period from birth (4BD) does not result in significant impairment. To test how these BD outcomes are reflected at the level of neuronal activity we compared the expression profile of the activity reporter gene zif268 in PMLS in three separate BD conditions. Adult and juvenile 4BD, 6BD and 2N2BD cats and age-matched controls were used. Cats were exposed to overnight darkness prior to 1-hour light stimulation and then sacrificed; kittens at the end of the BD period, adults after 2 years of visual training upon BD. In situ hybridization was applied using an oligonucleotide probe complementary to the nucleotides encoding amino acids 2-16 of the rat zif268 gene. For 4BD and 2N2BD kittens the zif268 mRNA level in PMLS was significantly elevated by 50%, as compared to age-matched controls. 6BD kittens also had elevated zif268 signals, but by 21%. Interestingly, zif268 expression in PMLS increases with age as in control kittens higher levels were observed after 6 than 4 months of age. In adult cats zif268 signals were highest in the 4BD group, while 2N2BD cats did not differ from controls. We infer that the developmental pattern of the motionsensitive area PMLS is affected by early BD. BD most likely prolongs the processes of cortical development, as zif268 mRNA levels in 4BD and 2N2BD kittens are equally high. Surprisingly, restoration of normal visual input in adult 2N2BD cats leads to normalization of activity levels in PMLS, while in the 4BD group it remains high. These results link high zif268 gene expression to behavioral performance.

Binocular deprivation reveals early plasticity-dependent region- and layer- specific zif268 expression profiles in cat primary visual cortex (area 17)

100%

Laskowska-Macios K., Zapasnik M., Hu T. T., Kossut M., Arckens L., Burnat K.

Acta Neurobiologiae Experimentalis

2011

tom 71

nr S

Binocular pattern deprivation (BD) alters visual cortex circuitry development, here for the first time studied via analysis of regionand layer-specific expression of the activity reporter gene zif268. We describe its profile in cat area 17 after BD in comparison to age-matched controls. Three BD conditions were applied; the first four (4BD) or six (6BD) months from eye-opening, and a late onset BD in the 3rd and 4th month of age, preceded by 2 months of normal vision (2N2BD). Cats were exposed to overnight darkness prior to 1-hour light stimulation and then sacrificed; kittens at the end of the BD period, adults after 2 years of visual training upon BD. Radioactive in situ hybridization was applied to analyze zif268 mRNA levels. Juvenile and adult BD cats showed elevated zif268 mRNA levels in peripheral area 17 compared to central area 17, while in controls the signal was similar throughout area 17. 2N2BD kittens had such a BD pattern only in layer IV. All juvenile control and BD kittens, except 4BD, showed a similar inter-laminar zif268 expression profile for central area 17. The least active was layer IV and the most active layer V/VI. Adult control and BD cats displayed such a pattern throughout area 17. Furthermore in BD kittens, layers IV and II/III had a higher level of zif268 mRNA than in control area 17. 4BD resulted in a distinctive elevation of the zif268 mRNA level: in adults in all peripheral area 17 layers as compared to controls; in juveniles in layer IV throughout area 17 and in central layer II/III compared to controls and other BD kittens. We conclude that the quality of visual input during the initial 4 months of life plays a crucial role in establishing the inter-laminar circuitry within primary visual cortex in cat. We suggest that early BD arrests the developmental processes in central and peripheral representations leading to a continued differential zif268 gene expression ratio in central versus peripheral area 17 into adulthood. Project co-financed by the European Union from the European Regional Development Fund within the frame of International PhD Projects Programme (MPD4-504).

Ograniczanie wyników

2 Acta Neurobiologiae Experimentalis

2 Arckens L.

2 Burnat K.

2 Hu T. T.

2 Kossut M.

2 Laskowska-Macios K.

2 Zapasnik M.

2 2011

Wyniki wyszukiwania

Effects of pattern deprivation on the development of the motion-sensitive posterior medial lateral suprasylvian (PMLS) visual area of the cat as revealed by zif268 gene expression

Binocular deprivation reveals early plasticity-dependent region- and layer- specific zif268 expression profiles in cat primary visual cortex (area 17)