Fig. 6. Expression of Myc (A) and cyclin D1 (B) in cerebellar homogenates of rat pups treated with L-NAME (60 mg/kg/day) for various neonatal intervals (P1-P3, P5-P7) and control pups. Total RNA was extracted from cerebella and equal amounts of RNA were used for real-time PCR performed with specific primers for Myc and cyclin D1, as described in the Materials and Methods section. These results, expressed as percentage of control at P3, are the mean ± s.e.m. of three different experiments performed in triplicate. ^*P<0.01, ^**P<0.001 compared with control, #P<0.01 compared with P3 control (Bonferroni's test after ANOVA). (C) Total cerebellar lysates from L-NAME-treated (P1-P3 and P5-P7) and control rat pups were immunoblotted with an antibody to Myc and quantification of bands was obtained with respect to ß-actin content. Values are the mean ± s.e.m. of three experiments. ^**P<0.001 compared to control, #P<0.01 compared to P3 control (Bonferroni's test after ANOVA). (D) Nuclear and cytoplasmic cerebellar lysates from L-NAME treated (P1-P3) and control rat pups were separately immunoblotted with an antibody to Myc and quantified respect to ß-actin content. Bars are the mean ± s.e.m. of three experiments. ^*P<0.05, ^**P<0.001 compared to cytoplasmic extracts, (Bonferroni's test after ANOVA). (E,F) Expression of Myc protein in the cerebellum of control (E) and P1-P3 L-NAME-treated (F) rat pups. Immunohistochemistry with an anti-Myc antibody reveals an increased stain in the external granular layer of L-NAME-treated pup. Bar, 40 µm.