Delayed and disturbed morphogenesis of the umbilical blood vessels in insulin-like growth factor-II deficient conceptuses (Igf2m+/p-).
Insulin-like growth factor-II (IGF-II) deficiency occurs when a conceptus inherits an inactive gene from the father (Igf2m+/p-): fetal wet weight is reduced to 60% of wild-type, with the decline starting at E11. The umbilical cord vessels of mutant and wild-type were compared. At E8.0-E8.5, the timing of somite formation and chorioallantoic fusion was not altered. At E14.5-E16.5, the left umbilical artery degenerated approximately 1 day later in Igf2m+/p- conceptuses when compared with the wild-type. In the common umbilical artery at E15.5, muscle volume was reduced by one third in IGF-II deficiency. Treating the umbilical arteries as ideal tubes, the values of radius(4)/length suggest that blood flow through the placenta may be reduced by more than half in the Igf2m+/p- conceptuses.
Ahmad
Amatul Mateen
AM
Department of Zoology, South Parks Road, Oxford OX1 3PS, UK.
Burns
Jason
J
Gardner
Richard
R
Graham
Chris
C
D000482:Allantois / Q000254:growth & development; D000818:Animals; D002823:Chorion / Q000254:growth & development; D005333:Fetus / Q000098:blood supply*; D007335:Insulin-Like Growth Factor II / Q000172:deficiency* / Q000235:genetics; D051379:Mice; D014469:Umbilical Arteries / Q000002:abnormalities* / Q000033:anatomy & histology / Q000196:embryology / Q000502:physiology; D014471:Umbilical Veins / Q000002:abnormalities* / Q000033:anatomy & histology / Q000196:embryology / Q000502:physiology
D007335:Insulin-Like Growth Factor II