Effects Of Maternal High Salt Diet During Gestation On He Renal Structures And Functions In The Adult Offspring Abstract

Background:Many evidences from basic science and clinical studies have demonstrated a relationship between high Na+ intake and cardiovascular diseases, such as hypertension. The"imprinting"theory (David Barker) hypothesizes that diseases in adults can originate from fetal periods. Researches showed that adult diseases could be programmed in fetal life. Whether high salt diet during pregnancy may induce damage in renal development in the fetus, and change renal functions in adult is still unknown. Thus, we used an animal model to determine the"imprinting"effect in the offspring exposed to prenatal high salt diet.Objectives:To investigate the impact on renal structures and functions in the adult offspring exposed to maternal high salt diet during gestation.Methods:Pregnant rats were fed with high salt food(8%NaCl)from gestation day 4 to 21, and the offspring were fed with normal food. Their body and kidney were weighted; the basal blood pressure were assessed in adult offspring;blood gases and electrolytes were determined with a Nova analyzer;plasma PRA, Angâ…¡, AVP, ALD and UN concentrations were measured by radioimmunoassay; water intake and sodium appetite of adult offspring were detected after injected subcutaneously with the diuretic Furosemide and 24h water deprivation; the ultrastructures of the kidney were examined by a transmission electron microscope; expression of AT1 and AT2 receptors in the kidney were assessed; mRNA and protein of Angâ…¡receptors (ATR) in the adult kidney were determined with real-time PCR and western-blot.Results:Comparing with the control group (fed with normal food during gestation period), the ratio of kidney weight/body weight is lower in the experimental group (fed with high salt food during gestation); plasma Angâ…¡, PRA, and ALD concentrations in the experimental group were significantly reduced, while plasma AVP and UN level were increased; Following subcutaneous injection of diuretic Furosemide and 24h water deprivation, the rats in the experimental group drank less water in 2 hours period; The ultrastructures and expression of mRNA and protein of ATR in the offspring kidney were also changed.Conclusions:Maternal high sodium diet during gestational periods may affect renal structures and body fluid regulations.