Localization of 125I-atrial natriuretic peptide (ANP) in the rat fetus.

In this in vitro autoradiographic study of ANP-binding sites in fetal rats, 125I-ANP bound to receptors in certain developing neural crest derivatives, including the boundary caps, dorsal root ganglia, and Schwann cells of peripheral nerves. Within the spinal cord, ANP receptors were localized in the roof plate and floor plate. The developing meningeal layer of the CNS, blood vessels, lung, liver, and wall of the herniated gut were also labeled. The topographical and temporal correlation of the appearance of ANP receptors with the developmental processes of the targets suggests that ANP in the fetus is multifunctional, and may be involved in diverse events such as gliogenesis, formation of axonal pathways or surfactant production.