Intrauterine growth restriction is a risk factor for cardiovascular disease in adulthood.
We have previously shown that intrauterine growth restriction caused by uteroplacental
insufficiency programmes uterine vascular dysfunction and increased arterial stiffness in adult
female rat offspring. The aim of this study was to investigate vascular adaptations in growth
restricted female offspring when they in turn become pregnant. Uteroplacental insufficiency was
induced inWKY rats by bilateral uterine vessel ligation (Restricted) or sham surgery (Control) on
day 18 of pregnancy. F0 pregnant females delivered naturally at term. F1 Control and Restricted
offspring were mated at 4months of age and studied on day 20 of pregnancy. Age-matched
non-pregnant F1 Control and Restricted females were also studied. Wire and pressure myography
were used to test endothelial and smooth muscle function, and passive mechanical wall
properties, respectively, in uterine, mesenteric, renal and femoral arteries of all four groups.
Collagen and elastin fibres were quantified using polarized light microscopy and qRT-PCR. F1
Restricted females were born 10–15% lighter than Controls (P <0.05). Non-pregnant Restricted
females had increased uterine and renal artery stiffness compared with Controls (P <0.05), but this difference was abolished at day 20 of pregnancy. Vascular smooth muscle and endothelial
function were preserved in all arteries of non-pregnant and pregnant Restricted rats. Collagen
and elastin content were unaltered in uterine arteries of Restricted females. Growth restricted
females develop compensatory vascular changes during late pregnancy, such that region-specific
vascular deficits observed in the non-pregnant state did not persist in late pregnancy.