Premium
In vitro modulation of L ‐arginine transport in trophoblast cells by glucose
Author(s) -
Eaton,
Sooranna
Publication year - 1998
Publication title -
european journal of clinical investigation
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.164
H-Index - 107
eISSN - 1365-2362
pISSN - 0014-2972
DOI - 10.1046/j.1365-2362.1998.00409.x
Subject(s) - trophoblast , arginine , endocrinology , medicine , insulin , in vitro , microcarrier , chemistry , mole , cell culture , biology , amino acid , fetus , biochemistry , cell , placenta , pregnancy , genetics
Background The uptake of the semi–essential amino acid, L ‐arginine, into trophoblast cells was measured with the aim of determining the effect of different glucose concentrations on L ‐arginine influx kinetics. Methods This study used a novel superfused microcarrier culture system of BeWo cells (an established choriocarcinoma cell line with many characteristics of normal human trophoblast) and a rapid, paired‐tracer dilution technique to measure unidirectional influx into the cells. Results At 10 mmol L −1 D ‐glucose, L ‐arginine unidirectional influx across the microvillous border of the cells was saturable with a K m of 1.14 ± 0.14 mmol L −1 and a V max of 121.36 ± 5.89 nmol mg −1 protein min −1 . When cells were preincubated for 24 h in the presence of 30 mmol L −1 D ‐glucose, there was a significant increase in the V max for L ‐arginine of nearly 30%. Similarly, preincubation in the presence of 1 mmol L −1 D ‐glucose and 12.5 mIU mL −1 human insulin reduced the K m for L ‐arginine influx by over 55%. Conclusion These data suggest that the modulation of placental transport of L ‐arginine by glucose and insulin could contribute to the fetal macrosomia observed in diabetic mothers.