Additional file 2: Supplementary Fig. 2 Relative abundances of polyamines in maternal and fetal plasma (a,b) and placental fluids. Agmatine and polyamines in plasma are expressed as concentrations (nmol/mL), and expressed as total amounts (concentration × volume) in placental fluids. Agmatine was most abundant in the plasma of both ewes and fetuses (a,b). Similarly, agmatine was most abundant in allantoic fluid (c). In amniotic fluid, total amounts of agmatine were similar to those for polyamines, except for putrescine, which was least abundant (d).