title: In situ morphology of fetal aortic isthmus following ductal constriction in rats.
abstract: To clarify the effect of experimentally increased blood flow to the aortic isthmus, in situ cross-sectional morphology of the aortic isthmus and the juxta-ductal descending aorta was studied in fetal rats. Indomethacin (10 mg/kg) was administered to 10 near-term pregnant rats, and fetuses were studied 4 and 24 h later with cesarean section, rapid whole-body freezing, sectioning on a freezing microtome in a plane perpendicular to the aortic isthmus, and photographing cross-sections. Fetuses without treatment served as controls. The ductus was constricted and its cross-sectional area was 12 +/- 3% (mean +/- SEM, % of control; p < 0.05 vs. control) at 4 and 24 h. The aortic isthmus was enlarged and the cross-sectional area was 146 +/- 5% at 24 h in response to the increased flow. These results support the concept that the size of the fetal aortic isthmus can change rapidly depending on the flow in late gestation.
authors.affiliation: Department of Pediatric Cardiology, Heart Institute of Japan, Tokyo Women's Medical College.
authors.forename: K
authors.initials: K
authors.lastname: Momma
authors.forename: M
authors.initials: M
authors.lastname: Ando
mesh_terms: D000818:Animals; D001011:Aorta / Q000187:drug effects / Q000196:embryology*; D001013:Aorta, Thoracic / Q000196:embryology; D001017:Aortic Coarctation / Q000188:drug therapy; D001783:Blood Flow Velocity; D003251:Constriction, Pathologic / Q000139:chemically induced; D004373:Ductus Arteriosus / Q000187:drug effects*; D005260:Female; D007213:Indomethacin / Q000494:pharmacology*; D008431:Maternal-Fetal Exchange; D011247:Pregnancy; D051381:Rats; D017208:Rats, Wistar
chemical_list: D007213:Indomethacin