To explore the impact of AT1 receptor blockade on skeletal muscle regeneration, we inhibited AT1 receptor activation in cryoinjured mice by treatment with irbesartan, not by genetic disruption of Agtr1a gene, to eliminate possible metabolic effects of hyperphagia and obesity in Agtr1a−/− mice20. This evidence concerns the gene AGTR1 and obesity due to melanocortin 4 receptor deficiency.