RESUMEN
Insulin resistance (IR) in dogs is suspected when hyperglycemia is present despite administration of insulin doses greater than 1.0 to 1.5 UI/kg. IR is caused by increases in counter regulatory hormones concentrations (glucagon, glucocorticoids, catecholamines and growth hormone). This study was conducted to investigate the use of aglepristone (RU 46534), a P4 receptor antagonist, for the treatment of IR diabetes mellitus in bitches during the luteal phase. All animals were treated with porcine insulin zinc suspension (Caninsulin) and aglepristone (Alizin) 10 mg/kg subcutaneously at day 1, 2, 9 and 17 from diagnosis. At day 5, no significant variation in glycemia was shown. At day 12 and 20, serum glucose concentrations were significant lower (p < 0.05). From day 12 the insulin dose was reduced to 0.8 IU BID. Insulin was reduced in the following weeks and glycemia was controlled.