Three-dimensional cultures of dissociated myenteric plexus as amodel for the development of the enteric nervous system

Failures in the development of the enteric nervous system (ENS) can lead to severe dis-eases, such as Hirschsprung`s disease or any other dysganglionosis. Trying to imitate the de-velopment of the ENS, the myenteric plexus, in vitro might give us a better understanding of the underlying problems and the chance to develop new diagnostic and even therapeutic ap-proaches. Myenteric plexus of newborn rats was isolated by enzymatical digestion, dissociated and cultivated either on glass coverslips, or in a three-dimensional gel of extracellular-matrix-components. Supplementing the culture media with the neurotrophins Glial-cell-line-derived-neurotrophic-factor (GDNF) or brain-derived-neurotrophic-factor (BDNF), alone or in com-bination, lead to differences in the growth behaviour of the individual culture. GDNF increased the survival, as well as the neurite outgrowth of the neurons, while BDNF had no obvious effect when administered alone. Only in combination with GDNF it in-creased the branching patterns of the neurites, indicating a higher degree of differentiation. These phenomena were seen on glass, as well as in the gel cultures. The only difference was, that cultures grown in the gels formed secondary ganglia which were similar to what is seen in more severe cases of dysganglionosis, while there was no specific reaggregation on glass. The degree of “artificial hypoganglionosis” varied, depending on the factors which were supple-mented to the media. Cultivating dissociated myenteric plexus in a three-dimensional environment seem to be a valuable model to imitate the development of the ENS, and so to investigate the effect respec-tively the lack of certain factors for the development of an intact and well working gastrointes-tinal innervation.