LEPR and obesity due to melanocortin 4 receptor deficiency: The contribution of each of these metabolic factors in obesity and/or MetS development is well known [25], [26], and it is conceivable that their alteration with ageing together with the hyperphagia resulting from the leptin receptor inactivation, participates in the development of the massive obesity and non-alcoholic hepatic steatosis found in SHHFcp/cp rats.