Calcium dependence of alpha-aminoisobutyric acid transfer in human bilaterally perfused placental lobules.
Human isolated bilaterally perfused placental lobules were employed to study the Ca++ dependence of materno-fetal transfer of the non-metabolisable amino acid, alpha-aminoisobutyric acid (AIB). Bilateral perfusion with Ca(++)-free Krebs' solution containing 2 mmol/l EDTA for 60 min resulted in a significant reduction in materno-fetal AIB transfer compared to controls perfused with normal Krebs' solution. However, bilateral perfusion with Krebs' solution containing: 2.5 mmol/l Ca++ and 2 mmol/l EDTA; 3.8 mmol/l Ca++ with no EDTA; or Ca(++)-free Krebs' solution alone did not produce significantly different materno-fetal AIB transfer compared to placentae perfused with normal Krebs' solution. The reduction in AIB transfer during perfusion with Ca(++)-free Krebs' solution with EDTA was partially restored with subsequent reperfusion with normal Krebs' solution for 90 min. These results suggest that AIB transfer in human perfused placental lobules is at least partially Ca(++)-dependent.
Krishna
B R
BR
Monash Perinatal Unit, Monash Medical Center, Clayton, Australia.
Gude
N M
NM
King
R G
RG
Brennecke
S P
SP
D000621:Aminoisobutyric Acids / Q000378:metabolism*; D001692:Biological Transport / Q000187:drug effects; D002118:Calcium / Q000494:pharmacology*; D004492:Edetic Acid / Q000494:pharmacology; D005260:Female; D006801:Humans; D007700:Kinetics; D010477:Perfusion; D010920:Placenta / Q000378:metabolism*; D011247:Pregnancy; D015203:Reproducibility of Results
D000621:Aminoisobutyric Acids; C100049:2-aminoisobutyric acid; D004492:Edetic Acid; D002118:Calcium