Calcium dependence of alpha-aminoisobutyric acid transfer in human bilaterally perfused placental lobules

Abstract

Human isolated bilaterally perfused placental lobules were employed to study the Ca++dependence of matemofetal transfer of the non-metabolisable amino acid, α-aminoisobutyric acid (AIB). Bilateral perfusion with Ca++-free Krebs' solution containing 2 mmol/1 EDTA for 60 min resulted in a significant reduction in matemofetal AIB transfer compared to controls perfused with normal Krebs' solution. However, bilateral perfusion with Krebs' solution containing: 2.5 mmol/1 Ca++and 2 mmol/1 EDTA; 3.8 mmol/1 Ca++with no EDTA; or Ca++-free Krebs' solution alone did not produce significantly different matemofetal AIB transfer compared to placentae perfused with normal Krebs' solution. The reduction in A..