Effect Of Ketamine Or Propofol Anesthesia In Early Pregnancy On The Expression Of N-methyl-d-aspartate Receptor Subunit2b (Nr2b) In The Offsprings’ Hippocampus Of Rats

Objiective: To study the effect of Ketamine or propofol anesthesia in earlypregnancy on the expression of N-methyl-D-aspartate Receptor Subunit2B（NR2B）in the offsprings’hippocampus of rats.Methods: Two hundred ten healthy SD rats,aged70days,weighing180-220g, wererandomly assigned to Ketamine ahesthesia group (group K),propfol ahesthesia group(group P) and control group (group C). On the5to7days of gestation, Ketam-ine orpropfol anesthesia was given，while in control group, Ketamine or propfol wasreplaced with eaqual volume physiological saline.According to the anesthesia time,rats in group K and group P were respectively divided into2hours subgroup(subgroup K2),4hours subgroup(subgroup K4), and8hours subgroup(subgroupK8), with30for each.The learning and memory function of offsprings (aged30days)were analyzed by Morris water maze.After Morris water maze experiment, theoffsprings were sacrificed. Real Time polymerase chain reaction was used to detectthe expression levels of N-methyl-aspartate receptor2B (NR2B) in the offsprings’hippocampus.Result: The escape latency of the offsprings’ in group K(K2subgroup, K4subgroup,K8subgroup) was significant longer than that in group C (P <0.05),while nosignificant difference could be seen in the escape latency of the offsprings’ amongK2, K4and K8subgroup(P>0.05).The escape latency in K8subgroup delayedsignificant earliest and the lasted time was the longest time, K4subgroup was in thenext place, and K2subgroup was in the last, and lasted for the shortest time.Thenumbers of crossing the platform by the offsprings in K2, K4, K8subgroup were1.89±0.37,1.78±0.46and1.79±0.47respectively,obviously less than that in groupC(2.96±0.62)(P <0.05). The time of traveling in second quadrant by the offspringsin K2, K4, K8subgroup were26.63±3.96,26.54±4.57and27.57±4.01srespectively,obviously shorter than group C(31.84±3.74s)(P <0.05).There was nosignificant difference could be seen in the numbers of crossing the platform and thetime of traveling in second quadrant by the offsprings’ among K2, K4and K8subgroup (P>0.05). There was no significant difference could be seen in the escape latency of the offsprings’ between P2subgroup and group C(P>0.05).The escapelatency of the offsprings’ in P4and P8subgroup was longer than that in group C(P<0.05).,while no significant difference could be seen ’ among P2, P4and P8subgroup (P>0.05).There was no significant difference could be seen in the numbersof crossing the platform and the time of traveling in second quadrant by theoffsprings between subgroup P2and group C(P>0.05). The numbers of crossing theplatform by the offsprings in subgroup P4and subgroup P8were1.93±0.45and1.78±0.46respectively,obviously less than that in group C(2.96±0.62)(P <0.05).Thetime of traveling in second quadrant by the offsprings in subgroup P4and subgroupP8were25.35±4.42s and26.89±2.74s respectively,obviously shorter than that ingroup C(31.84±3.74s)(P <0.05).There was no significant difference could be seen inthe numbers of crossing the platform and the time of traveling in second quadrant bythe offsprings’ among P2, P4and P8subgroup (P>0.05). The expression levels ofNR2B mRNA in the offsprings’ hippocampus in K2, K4and K8subgroup were0.4215±0.3809,0.3493±0.2634and0.3325±0.2856,obviously less than that in groupC(1.0177±0.2300)(P <0.05),while no significant difference could be seen among K2,K4and K8subgroup (P>0.05). The expression levels of NR2B mRNA in theoffsprings’ hippocampus in P2, P4and P8subgroup were0.6599±0.5744,0.6306±0.4593and0.6740±0.4194, showed no significant difference when compared withgroup C(1.0177±0.2300)(P>0.05). There was no significant difference could beseen in the expression levels of NR2B mRNA among P2, P4and P8subgroup (P>0.05).Conclusion： Under the experimental condition, Ketamine or propofol anesth-esiacould damage the spatial learning and memory function of the SD rat’s offspr-ings’,and time-effect relationship is existence.The mechanism of Ketamine is down-regulate expression of learning and memory positive regulation factors NR2BmRNA, The mechanism of propfol has no connection with the expression of NR2BmRNA,it needs further study.