We previously reported reduced aortic elasticity and endothelium dependent vasodilatation in six month old offspring of rats fed a diet rich in animal fat in pregnancy and suckling (Armitage et. al., 2004). Here we examine aortic function in second-generation offspring to assess whether deficits are transgenerational. Sprague Dawley rats were fed a fat rich diet (20% animal lard and 5% corn oil w/w) or a control diet (5% corn oil w/w) for 10 days prior to mating, pregnancy and during suckling. Offspring (from control OC, and fat fed dams, OHF) were weaned at 21 days of age and fed a standard rat chow (RM1, SDS, UK) to 110 days of age then OC and OHF were fed a standard breeding diet (RM3, SDS, UK) for 10 days prior to mating, during pregnancy and suckling. Second generation offspring (OC2 and OHF2, n=14 per group, equal ♂and ♀) were weaned at 21 days of age and fed RM1 until six months of age then humanely sacrificed (rising CO₂ concentration). Thoracic aorta was dissected, cut into rings of 2.5mm length and mounted on an organ bath in physiological salt solution (PSS) at 37°C with a basal force of 5mN. Vessels were subjected to a run-up procedure, and dose response curves to phenylephrine (3×10^-9 – 10^-5 M), ACh (3×10^-9 – 10^-5 M, with and without 10^-3 M L-NAME), and nitric oxide (10^-8 – 10^-4 M) were conducted. PSS was then replaced with Ca free PSS and vessels subjected to a length- force curve (cumulative 500, 200, 50 μm). Dose response curves were analysed by RM ANOVA and fitted EC₅₀ values by ANOVA. For all analyses, gender was incorporated as an independent variable in the initial model but removed if not significant. Bodyweights did not differ between OC2 and OHF2 groups, however brain and kidney mass were increased in OHF2 compared with OC2 animals (P<0.02). There was no difference in aortic contractility to phenylephrine (RMANOVA, P<0.45, EC₅₀ OC2 -7.9±0.1 vs OHF2 -7.3|±0.1, P<0.09). ACh response was not different between groups (RMANOVA, P<0.1, EC₅₀ OC2 -7.5±0.1 vs OHF2 -7.6±0.1, P<0.2). Nitric oxide responses did not differ between groups (RMANOVA, P< 0.09, EC₅₀ -6.7±0.2 vs -6.6±0.3, P<0.9). Length-force curves did not differ between groups (RMANOVA, P<0.68). There were significant differences in some organ weights but otherwise second-generation offspring off fat fed dams did not show any alteration in aortic function. This lack of significance was not due to insufficient power and suggests that the vascular deficits seen in the first generation offspring (Khan et. al., 2003) are not transmitted across further generations.