Table 3.11 - Rerouting of Circuits at Birth.
|Umbilical Art's||closure||2 - 4 min.||smooth muscle contraction (PO2 & cold); ligature|
|Umbilical Vein||closure||2 - 4 min.||same|
|Ductus Venosus||closure||hrs. - day||passive mechanical; smooth muscle contraction?|
|Foramen Ovale||closure||minutes||pressure in LA exceeds that in RA|
|Pulm. Vasculature||opening||minutes||smooth muscle relaxation (increased PO2); smooth muscle atrophy|
|Ductus Arteriosus||closure||hrs. - day||smooth muscle contraction with increased PO2|
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