Correlation-based plasticity weakens the deprived eye responses, while homeostatic synaptic scaling normalizes total postsynaptic drive by increasing the responses to both eyes (Frenkel and Bear 2004; Mrsic-Flogel et al. 2007; Kaneko, Stellwagen et al. 2008; Kaneko, Hanover et al. 2008; Kaneko et al. 2012).
Although the experimental paradigm is rather similar, molecular mechanisms underlying 'juvenile' and 'adult' OD-plasticity are different: in juvenile mice, OD-shifts are mostly mediated by reductions in deprived eye responses while adult plasticity is predominantly mediated by an increase in open eye responses in V1 (Hofer et al., 2006; Espinosa and Stryker, 2012; Levelt and Hübener, 2012).
As without treatment, the preserved OD plasticity of rl−/−mice was mediated by a reduction of deprived eye responses after MD (1.3 ± 0.1, ANOVA, p < 0.001) while open eye responses did not change compared to rl−/− mice without MD (1.7 ± 0.1, ANOVA, p > 0.05).
Interestingly, in the three MD groups treated with GM6001, deprived eye responses were reduced compared to GM6001-treated mice without MD (PT+GM6001, 2.3.
However, treatment in this study only partially prevented the OD-shift, as there was no effect on the reduction of deprived eye responses (Spolidoro et al., 2012).
There was a significant reduction in deprived eye responses in V1 in the GM6001- but not vehicle-treated mice after MD (B ).
In addition, the mechanism underlying OD plasticity in rl−/− mice was different from WT: in adult rl−/− mice, OD shifts were mediated by a reduction in deprived eye responses in V1.
A reduction in deprived eye responses in V1 is mostly observed in juvenile rodents after 3-4 days of MD (Gordon and Stryker, 1996), unless different raising conditions are used such as enriched environment or running wheel (Greifzu et al., 2014; Kalogeraki et al., 2014).
miR395s play a very important roles in the sulfur-deprived response in higher plants [ 19, 20] where miR395 regulates sulfate distribution and metabolism in the plant cells.
However, no patients with PR shifted to PMD, suggesting that patients with a distinct treatment response on CT would theoretically not be deprived treatment if morphologic response assessment was to be replaced with metabolic in future clinical trial settings.
Second, there is possible response bias, particularly due to the difficulties of recruiting younger men from the most deprived areas, although the response rate at about 25% is not unusual for population based surveys [ 60, 61].
