†These authors contributed equally.
Academic Editor: Graham Pawelec
Background: Dietary
supplementation with L-arginine (Arg) has been shown to increase the volume of
fetal fluids in gestating swine. Aquaporins (AQPs), known as water channel
proteins, are essential for embryonic growth and development. It was not known if
Arg mediates water transport through AQPs in porcine conceptus trophectoderm
(pTr2) cells. Methods: pTr2 cells derived from pregnant gilts on day 12
of gestation were cultured in customized Arg-free Dulbecco’s modified Eagle’s Ham
medium (DMEM) supplemented with either 0.00, 0.25, or 0.50 mM Arg.
Results: Arg treatment increased water transport and the expression of
AQP3, which was abundantly expressed in pTr2 cells at both the mRNA and protein
levels. Arg also increased the expression of iNOS and the synthesis of nitric
oxide (NO) in pTr2 cells. The presence of N