Impairment of insulin-stimulated glucose uptake is considered the most consistent change that develops early in the hearts of animal models of insulin resistance.26 This change occurs as a consequence of both reduced glucose transporter 4 (GLUT4) protein expression and impaired translocation.27 In this regard, while melatonin’s effects have been extensively reported in other insulin-sensitive organs, such as the hypothalamus, skeletal muscle, liver and adipose tissue,25,28-30 it is unclear whether melatonin affects cardiac glucose uptake in the insulin-resistant state. This evidence concerns the gene INS and Insulin resistance.