This is consistent with existing literature showing that the expression of OBRb mRNA in liver is dependent on the body weight.22 Previous study also demonstrated that cultured astrocytes expressed mRNA for the leptin receptor, which increased in response to leptin treatment.23 Thus, the higher level of expression of OBRb in the NP tissue seems to be related to hyperleptinemia in obesity. This evidence concerns the gene LEP and obesity due to melanocortin 4 receptor deficiency.