5-HT2B receptors have been found to be present in both rodent and human tissues, particularly in the cardiovascular system, gastrointestinal tract, bone, and central nervous system2. Only low expression levels are found in brain and blood. The highest expression levels are found in the stomach fundus.nOver-expression of 5-HT2B receptors in hearts of transgenic mice results in cardiac hypertrophy and decreased ventricular function due to enhanced extracellular matrix (ECM) and remodeling. Likewise, genetic deletion of 5-HT2B receptors was shown to lead to ventricular dilation and incomplete cardiac development
