Npr2 mutant mice show vasodilation and undeveloped adipocytes in mesentery

Objective The biological importance for the signaling of C-type natriuretic peptide (CNP) and natriuretic peptide receptor B (NPR-B) has been recognized. However, the details remain unclear and are debatable. The Npr2 is a gene of NPR-B, and we previously reported a unique phenotype of a spontaneous mutant mouse lacking Npr2 ( Npr2 slw/slw ), such as severe ileus-like disorder with bloodless blood vessels. In this study, we analyzed the bloodless mesenteric vascular morphology of Npr2 slw/slw by histological observation to clarify the effects of the CNP/NPR-B signal deficiency. Results Blood vessels in the mesentery were clearly dilated in the preweaning Npr2 slw/slw mice. Additionally, in the Npr2 slw/slw mice, the lacteals were partially dilation or randomly direction mucosal epithelial cells in villi, and mesenteric adipocytes were undeveloped. These findings provide important information for understanding the role of CNP/NPR-B signals on intestine with mesentery.