Figure 2. Enhanced thalamocortical plasticity in K^bD^b-/- mutant mice.

(A) Schematic of connections in mouse visual system: thalamocortical axon terminals innervate layer 4 of cortex. Below, transneuronal transport of H³–proline following intraocular injection reveals (age P34; Experimental procedures) a broad contralateral signal (left), and smaller ipsilateral patch (right) in layer 4. Scale=1500μm. (B) Higher magnification of representative sections from K^bD^b+/+ (top) and K^bD^b-/- (bottom) mice. Arrows indicate measurement borders used. Scale = 450μm. (C) Population averages for width ± sem of layer 4 label for each genotype after ME. P<0.05; (Mann-Whitney U test).