On the other hand, [Pyr1]apelin-13 inhibits insulin secretion in rat insulinoma cells (INS-1) (Guo et al., 2009), while intravenous administration of apelin-36 inhibits insulin secretion in mice (Sörhede Winzell et al., 2005) (see section XI.E). This evidence concerns the gene INS and pancreatic insulinoma.