Programmed aortic dysfunction and reduced Na+,K+-ATPase activity present in first generation offspring of lard-fed rats does not persist to the second generation

We have previously reported that male and female offspring of Sprague-Dawley rats fed a diet rich ( approximately 50% of caloric intake from fat) in animal fat ( lard) during pregnancy and suckling ( OHF) demonstrate cardiovascular dysfunction, including blunted endothelium-dependent vasodilatation in the aorta as well as reduced renal Na+, K+-ATPase activity. Cardiovascular dysfunction has been reported in other models of developmental programming and some researchers describe transmission from F-1 to F-2 generations. Here we report a study of vascular function, as assessed in isolated rings of aorta mounted in an organ bath, and renal Na+, K+-ATPase activity in 6-month-old male and female F-2 offspring of lard-fed and control-fed ( OC) dams ( n = 13 per diet group). An increase in brain ( OC 0.61 +/- 0.01% versus OHF 0.66 +/- 0.02% of bodyweight) and kidney weights ( OC 0.32 +/- 0.01% versus OHF 0.37 +/- 0.01% of bodyweight) was observed in female F-2 offspring of lard-fed dams compared with F-2 controls ( P < 0.03). Constrictor responses to phenylephrine in the aorta were not different from F-2 controls ( repeated measures ANOVA, P = 0.85). Also, endothelium-dependent dilator function, as assessed by responses to acetylcholine ( repeated measures ANOVA, P = 0.96) and passive distensibility in the absence of extracellular calcium ( repeated measures ANOVA, P = 0.68), was similar. Additionally, renal Na+, K+-ATPase activity was not statistically different from that observed in control animals ( ANOVA, P = 0.89). Although a maternal diet rich in animal fat has deleterious effects on parameters of cardiovascular risk in F-1 animals, it does not appear that disorders previously reported in the F-1 generation are transmitted to the F-2 generation.