Analysis of the effects of endothelin-3 on the development of neural crest cells in the embryonic mouse gut.
OBJECTIVE
Mutations in the endothelin-3 (ET-3) and endothelin-B receptor (EDNR-B) genes cause terminal colonic aganglionosis in mice and are linked to Hirschsprung's disease. These experiments are designed to determine if the development of terminal enteric ganglia depends on changes in proliferation, apoptosis, or differentiation of enteric neural crest (NC) cells in response to ET-3.


METHODS
Gut from embryonic lethal-spotted mice (lacking ET-3) and controls were investigated in vivo. NC-derived cells were identified immunohistochemically and their proliferation, apoptosis and differentiation monitored by bromodeoxyuridine incorporation, the terminal deoxytransferase poly dU nick end labelling (TUNEL) reaction, and appearance of neuronal nitric oxide synthase (NOS), respectively.


RESULTS
No differences in apoptosis or proliferation of NC cells were apparent between lethal-spotted embryos and controls. Although no temporal differences in the differentiation of NOS neurones were evident, these cells appeared more cranially in the gut in the absence of ET-3 than in controls.


CONCLUSIONS
ET-3 has no detectable influence on proliferation, apoptosis, or timing of differentiation of NC-derived cells in the gut. However, the more proximal location of differentiated neurones in the absence of ET-3 is consistent with a restricted role in migration of NC-derived cells.
Woodward
Mark N
MN
Department of Child Health, the University of Liverpool, Liverpool, England, UK.
Sidebotham
Emma L
EL
Connell
M Gwen
MG
Kenny
Simon E
SE
Vaillant
Camille R
CR
Lloyd
David A
DA
Edgar
David H
DH
D000818:Animals; D017209:Apoptosis; D002454:Cell Differentiation; D002455:Cell Division; D003106:Colon / Q000166:cytology / Q000196:embryology* / Q000378:metabolism*; D019334:Endothelin-3 / Q000235:genetics / Q000378:metabolism*; D017615:Enteric Nervous System / Q000166:cytology / Q000196:embryology* / Q000378:metabolism*; D051379:Mice; D009432:Neural Crest / Q000166:cytology / Q000196:embryology* / Q000378:metabolism*
D019334:Endothelin-3