Effects of water-electrolyte metabolism related to renin-angiotensin system and imprinting in the offspring rats induced by maternal hypoxia during pregnancy
Objective To determine the effects of perinatal exposure to hypoxia on water-electrolyte metabolism related to rennin-angiotensin system (HAS) and "imprinting" effects in the offspring. Methods SD pregnant rats were individed into two groups randomly and were given different treatments. Fetal body weight, brain weight were measured at gestation 21 day (GD21). Blood gases, electrolytes and plasma osmotic pressure of both fetus and five-month old offsprings were measured. Intake of the 1.8% NaCl and water was measured following subcutaneous injection hypertonic saline in the offsprings, and an-giotensin receptors in the brain were determined. Results Maternal hypoxia during gestation significantly decreased GD21 fetal body weight, brain weight and plasma PO,and S03% level, but there were no different in offsprings. And there was no different of blood Na + /K+ concentrations and plasma osmolality either in fetus or in adult offspring rats regardless of perinatal exposure to hypoxia. To the offsprings following perinatal exposure to hypoxia, their salt appetite was significantly increased by subcutaneous injection hypertonic saline. Furthermore, in the forebrain of the offsprings with perinatal exposure to hypoxia, expression of angiotensin AT2 R but AT, R was reduced, and the ratio of AT, R/AT2 R was significantly increased compared to control offspring. Conclusion The results showed that stimulated salt intake can be affected by exposure to hypoxia in fetal origins, and the changed behavior was associated with the remodeled expression of AT5 and AT2 receptors in the forebrain of the offspring.
hypoxia during gestationfetal and offspringrennin-angotensin systemwater-electrolyte metabolism