IntroductionPrevious studies from our laboratory demonstrated that dietary salt overload and salt restriction during pregnancy were associated with cardiac and renal structural and/or functional alterations in adult offspring. The present study evaluated renal and cardiac structure and the local renin-angiotensin system in newborns from dams fed high-, normal- or low-salt diets during pregnancy.MethodsFemale Wistar rats were fed low- (LS, 0.15% NaCl), normal- (NS, 1.3% NaCl) or high- (HS, 8% NaCl) salt diets during pregnancy. Kidneys and hearts were collected from newborns (n = 6-8/group) during the first 24 hours after birth to evaluate possible changes in structure using stereology. Protein expression of renin-angiotensin system components was evaluated using an indirect enzyme-linked immunosorbent assay (ELISA).ResultsNo differences between groups were observed in total renal volume, volume of renal compartments or number of glomeruli. The transverse diameter of the nuclei of cardiomyocytes was greater in HS than NS males in the left and right ventricles. Protein expression of the AT1 receptor was lower in the kidneys of the LS than in those of the NS and HS males but not females. Protein expression of the AT2 receptor was lower in the kidneys of the LS males and females than in those of the NS males and females.ConclusionHigh salt intake during pregnancy induced left and right ventricular hypertrophy in male newborns. Salt restriction during pregnancy reduced the expression of renal angiotensin II receptors in newborns.

ObjectiveThis study aims to evaluate a possible influence of high‐ or low‐ salt intake during pregnancy on renal structure and renin‐angiotensin system in neonates in Wistar rats.MethodsPregnant rats were fed with normal, high or low‐salt diet (NR, HO and HR groups, respectively) from the first day of pregnancy until delivery. Kidneys of the newborns (6‐8/group) were collected in the first 24 hours of life. Total renalvolume (stereology) and kidney renin‐angiotensin system (indirect ELISA) were evaluated.Results (mean±SEM, p<0.05) HO NR HR Statistical analysis Dams weight (g) 351±23* 377±36 386±42 p&lt;0.05 vs HR Liter size (n) 14±0.82 14±0.65 14±0.53 NS Newborns Body weight (g) male 5.37±0.09* 6.47±0.07 6.45±0.08 p&lt;0.0001 vs NR and HR female 5.13±0.07* 6.05±0.09 5.99±0.08 p&lt;0.0001 vs NR and HR kidney weight (g) male 9.43±0.27 9.91±0.21 9.25±0.37 NS female 10.22±0.32 9.99±0.22 9.66±0.22 NS kidney volume (mm³) male 7.04±0.47 7.44±0.22 8.20±0.46 NS female 6.73±0.61 5.84±0.44 7.25±0.98 NS ANG II (%) male 75±6.33* 100 68.1±4.05* p&lt;0.05 vs NR ACE (%) male 95.4±13.5 100 82.5±6.68 NS ConclusionLow salt intake during pregnancy is associated with low birth weight. Renal angiotensin II content compared normal salt fed dams is lower in newborns from salt overloaded and restricted dams during pregnancy.