Lifespan and Glucose Metabolism in Insulin Receptor Mutant Mice

Figure 2

The blood glucose and serum insulin concentrations in 𝐼𝑟^P1195L/wt mice. (a) The blood glucose concentrations of fasting mutant male and female mice were assessed. All 𝐼𝑟^P1195L/wt mice exhibited blood glucose concentrations within the same range as the 𝐼𝑟^wt/wt mice (𝑛=6-10 for each genotype). (b) The serum insulin concentrations were determined in the nonfasting state of 4- and 9-month-old 𝐼𝑟^wt/wt and 𝐼𝑟^P1195L/wt mice (𝑛=7 for each genotype). (c) The serum insulin concentrations were determined in the fasting state of 25-month-old 𝐼𝑟^wt/wt and 𝐼𝑟^P1195L/wt mice (𝑛=5 for each genotype). The insulin concentrations were significantly increased in both female and male 𝐼𝑟^P1195L/wt mice compared with the 𝐼𝑟^wt/wt mice. (d, e) The histochemical analyses of the pancreas of 𝐼𝑟^P1195L/wt mice. (d) The 𝐼𝑟^P1195L/wt male mice exhibited extensive enlargement of the Langerhans islets compared to 𝐼𝑟^wt/wt mice. (e) In addition, the size of islets in 𝐼𝑟^P1195L/wt female mice was larger than in 𝐼𝑟^wt/wt female mice. The scale bars indicate 200 μm. *𝑃<0.05, **𝑃<0.005 by Student’s 𝑡-test.

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