Effects And Mechanism Of Maternal Hypoxia During Gestation On The Learning And Memory In The Offspring

Part1Effects of hypoxia during gestation on development of fetalbrainObjective: To determine the effects of hypoxia during fetal briandevelopment.Methods: Time-dated pregnant SD rats were randomly divided into twogroups: control and hypoxia group (n=8, each group). Animals in the hypoxia groupwere housed in a mionectic chamber with oxygen level maintained at10.5%from day4to day21of gestation, The normoxic control group was housed in the similarchamber filled with only room air. Fetal body weight and brain weight were measuredat gestation21day; Blood gases and electrolytes were determined with a Novaanalyzer; Plasma osmolality was determined with an advanced digmatic osmometer;Protein level of NR2in the brain were measured with western blot. Result: hypoxiaduring gestation significantly decreased fetal body weight and brain weight, decreasedplasma pO2and SO2%level. Others blood gas index (pH,Na+,K+,Osm,pCO2,Hb,Hct,Glu and Lac) were not changed. In addition, the NR2protein levels werereduced in the fetal brain in hypoxia groups. Conclusion: Hypoxia during gestationaffected fetal development and blood values. Part2Effects of hypoxia during gestation on learning and memoryin offspring ratObjective: To determine the effects of hypoxia during gestation on learning andmemory in the offspring rat. Methods: The offspring (4-5months) body and brain wereweighted; Learning and memory were test with water maze; Protein level of NR2in the brain were measured with western blot. Result: The offspring body and brain weights,and blood gas index were the same between the control and experimental groups;However, the cap ability of learning and memory in the hypoxia groups as significantlydecreased, while NR2levels were decreased. Conclusion: Maternal hypoxia duringgestation influenced the ability of learning and memory in offspring asscociated withchange is NR2in the brain. Part3Effects of NMDA and AMPA on learning and memory in theoffspring exposed to prenatal hypoxia in gestationObjective: To determine the effects of NMDA and AMPA on learning and memoryin the offspring exposed to prenatal hypoxia in gestation. Methods: The adultoffspring (4-5months) of two groups were randomly chosen and i.c.v injected withNMDA,AMPA or aCSF in lateral ventricles, then ability of learning and memory wastested. Result: Following i.c.v NMDA and AMPA the ability of learning and memorywas significantly increased in the offspring of hypoxia group. Conclusion: NMDA canimprove the ability of learning and memory in offspring exposed to prenatalhypoxia.but,AMPA have no effect on learning and memory.