Intraperitoneal injection of liraglutide (100 μg/kg) significantly decreased the expression of hypothalamic 5-HT2A receptors compared with saline controls but did not affect the expression of hypothalamic 5-HT2C receptors 1 h after injection (Figure 3). These findings demonstrate that GLP-1 receptors downregulate expression of hypothalamic 5-HT2A receptors in mice.