Effect of maternal oxygen therapy on placental calcium transport in intrauterine growth retarded rats.
OBJECTIVE
We tested the hypothesis that continuous maternal oxygen (O2) therapy leads to an increase in fetal survival, improvement in fetal growth, and correction of decreased placental calcium (Ca) transport, in pregnant rats who underwent uterine artery ligation.


METHODS
We measured on Day 21 of pregnancy, the unidirectional maternofetal clearance of 45Ca (Kmf45Ca) and 51Cr-EDTA (Kmf51Cr-EDTA) across in-situ perfused placentas of rats randomized on Day 17 to a modified Wigglesworth (bilateral uterine artery ligation) procedure (group WW, n = 8), to modified Wigglesworth and supplemental maternal O2 treatment (FiO2 0.40) (group WWO2, n = 8), or to a sham operation (group Sh, n = 8). Kmf51Cr-EDTA provides a measure of placental "porosity" or passive permeability.


RESULTS
Maternal O2 therapy did not improve fetal survival, fetal growth, or placental Ca transport. CONCLUSION AND SPECULATION: Bilateral uterine ligation in the pregnant rat leads to IUGR and decreased placental Ca transport which cannot be corrected by maternal O2 therapy.
Mimouni
F
F
Department of Pediatrics, Maimonides Medical Center, Brooklyn, New York 11219, USA.
Mughal
Z
Z
Tsang
R C
RC
Hammond
G
G
D000818:Animals; D001692:Biological Transport; D002118:Calcium / Q000378:metabolism*; D005260:Female; D005313:Fetal Death / Q000517:prevention & control; D005317:Fetal Growth Retardation / Q000378:metabolism / Q000628:therapy*; D005865:Gestational Age; D010100:Oxygen / Q000008:administration & dosage / Q000627:therapeutic use*; D010920:Placenta / Q000378:metabolism*; D011247:Pregnancy; D051381:Rats; D017207:Rats, Sprague-Dawley
D010100:Oxygen; D002118:Calcium