Animals were maintained on a standard diet and housed under a

12-hour light/dark cycle. The investigation conformed to the Guide for the Care and Use of Laboratory Animals published by the National Institutes of Health (publication 86-23, revised 1985). SkHep-1 cells plated onto coverslips were fixed with 4% paraformaldehyde. Confocal immunofluorescence (IF) was performed as previously described.[18, 19] SkHep-1 cell and Holtzman rat hepatocyte immunoblottings and separation of nuclear and non-nuclear protein extracts were carried out as previously described.[11] Cell-surface biotinylation and streptavidin pull-down were performed, with modifications, as previously described.[14] Plasmids were generated,[14] and adenoviral constructs were amplified and purified as previously described.[20] Ca2+ signals were detected and measured by time MAPK Inhibitor Library solubility dmso lapse confocal microscopy as described.[14, 18, 19] Validated small interfering RNAs (siRNAs) for clathrin heavy chain (cla) and caveolin-1 (cav) were obtained from Ambion (Austin, TX). SkHep-1 cells were transfected with 5 nM of each siRNA using Lipofectamine 2000, according to the

manufacturer’s instructions (Gibco, Grand Island, NY). Cells were used 48 hours after transfection. Cell proliferation was measured by bromodeoxyuridine (BrdU) incorporation using an enzyme-linked immunosorbent assay (Roche Applied Science, Indianapolis, IN), according to the manufacturer’s instructions. Two-thirds (partial) hepatectomy (PH) was performed Selleck Panobinostat selleckchem on adult male Holztman rats as previously described.[21] Immunohistochemistry (IHC) was performed following standard methods for microwave antigen retrieval.[22] Glucose content in the blood was measured using an enzymatic colorimetric assay method (Analisa, Belo Horizonte, Brazil), according to the manufacturer’s instructions. Glycogen content from liver samples was determined by a phenol-sulfuric acid method, as described by Dubois

et al.,[23] with modifications. Results are expressed as mean values ± standard deviation (SD). PRISM software (GraphPad, La Jolla, CA) was used for data analysis. Groups of data were compared using the Student t test or one-way analysis of variance (ANOVA; which was used because data sets included only one independent variable), followed by Bonferroni’s post-tests, and P < 0.05 was taken to indicate statistical significance. Detailed and additional methods are available in the Supporting Materials and Methods. Translocation of the IR to the nucleus has been observed in primary rat hepatocytes.[11] To investigate whether the IR translocates to the nucleus in the SkHep-1 human hepatoma cell line as well, cells were analyzed by confocal IF microscopy to monitor localization of the IR before and after insulin stimulation. This liver cell line was used because, as in primary hepatocytes, it contains Ca2+-signaling machinery in both the cytoplasm and the nucleus.