Considering the glucocorticoid effects on inflammatory response inhibition as well as the IGF-1 and glucose uptake (peripheral insulin resistance), the IRS-1 mRNA expression was only affected by dexamethasone (1.25 and 2.5 mg/kg/day for 10 days), probably leading to a significant impairment of insulin signaling, although we have not evaluated IRS1/2 protein expression, insulin production, glycaemia, or muscle glucose uptake. This evidence concerns the gene IRS1 and Insulin resistance.