HTR1B and obesity due to melanocortin 4 receptor deficiency: This study aims to analyse central mRNA expression levels of 5-HT receptors related to feeding (5-HT1A, 5-HT1B, 5-HT6, 5-HT2C) within this mouse model of obesity (ob/ob) and in particular to analyse if there is an altered 5-HT2C receptor editing profile within the obesity phenotype, by analysing the expression of partially as well as fully edited 5-HT2C receptor isoforms.