Fig. 2. Effects of the inhibitory action of U0126 and PD98059 in retino-geniculate connections. Intracerebroventricular (ICV) injection of U0126 (500 µM, P5 rats n=4, B) or PD98059 (1 mM, n=4, C) drastically reduces ERK activation in the dLGN with respect to the saline injection (n=3, A). (D-G) U0126 does not affect pCaMKII or pAkt expression. ICV injection of saline (D) or 1 µl of 500 µM U0126 (E) does not block CaMKII phosphorylation in the dLGN. Also pAkt levels in the dLGN remain unchanged after ICV injection of saline (F) or U0126 (G, P4 rats, n=5 for each treatment). (H-M) Distribution of retinal projections in the dLGN of P9 rats that received beads-U0126 or beads-vehicle ICV injections. (H,H') Projections from the contralateral eye expand filling the entire dLGN. (I) The relative contralateral area of U0126-treated animals (n=6) is significantly larger than that of control animals (n=5; Student's t-test, P<0.05). (J,K) Ipsilateral projections expand occupying an area twice greater than that of control animals (Student's t-test, P<0.05). (L,M) The projections coming from the two eyes largely overlap in the U0126-treated animals. Error bars depict the s.d. Dashed lines indicate the relative eye-specific areas in normal P9 rats. Scale bars: 100 µm for A-G; 200 µm for H,J,L; 100 µm for H'.