Fig. 4.
Insulin-dependent glucose metabolism in 6-month old wild-type (WT) and PIK3CBK805R/K805R mice (KR). Statistical significance: * P < 0.05, ** P < 0.01, ** P < 0.001. A) Blood glucose in random fed mice (n=9 per genotype). B) Insulin concentrations in the serum of random fed mice (n=9 per genotype). C) Blood glucose in fasted mice (wild type, n=9; KR, n=6). D) Glucose tolerance test (n=5 per genotype). E) Insulin tolerance test (n=7 per genotype). F) Insulin concentration in serum of glucose-treated fasted animals. G) Analysis of pancreatic islet size. Left: histological sections of hematoxylin-eosin (H & E) stained pancreata. Center: quantification of islet area (n=4 per genotype). Right: immunofluorescence with antibodies directed against insulin (Ins; red) and against glucagon (Gcn; green). Nuclei were stained with bisbenzimide (DNA; blue). Bars represent 100 μm. H) Histology of a representative liver section of the indicated mice stained with the periodate-Schiff (PAS) stain, recognizing carbohydrates. Measurement of % of PAS positive pixels: WT: 7.3 ± 0.9; KR: 2.27 ± 0.4. I) Glycogen levels in the liver of randomly fed 24 week-old mice (n=7). J) Pyruvate challenge of wild-type (WT) and PIK3CBK805R/K805R (KR) mice. A bolus of 2 g/kg was administered intraperitoneally in 24 week-old mice fasted for 16 hours and blood glucose was measured at the indicated time points (n=5).