Motivated by the findings of our previous research on changes in Rb levels in obesity, as well as the established role of Rb in neurophysiological processes and brain activity as shown by other studies, the aim of the present paper is to investigate whether Rb levels in brain regions directly or indirectly involved in appetite regulation are altered by excessive body fat in obese animals. The gene discussed is RB1; the disease is obesity due to melanocortin 4 receptor deficiency.