Study Of Damage Of Anesthesia And Surgery On Cognitive Function Of Rats And Its Expression Of MMP-9

Objective: To detect MMP-9expression of POCD model rats in serum and genetranscription of MMP-9in hippocampus; analyze the effects on narcotic postoperativecognitive dysfunction, and to explore the signaling pathways which regulateexpression of MMP-9in POCD model rats in serum.Methods: SD rats were trained in water maze for six days, randomly dividedinto three groups, group A as control group (15), group B as anesthesia group (35) andgroup C as surgery group (35). Rats were fasten for one day.0.125%bupivacaine wasused to infiltration anesthetize in abdomen in Group A. SD rats of group B weretreated with same way first, then treated with2%isoflurane anesthetize, andendotracheal intubation and mechanical ventilation were used on SD rats(1mL/100g,R70-110/min),2%isoflurane anesthetize for2h, re-abdomen0.125%bupivacaineinfiltration anesthesia. SD rats of group C were treated with same way first, thenlaparotomy for2h. The SD rats were treated with the flip of the Morris water mazetest was used to detect the spatial memory and learning ability on the day beforesurgery, and postoperative1,3,5,7days. Sacrificed rats after the test, ELISA assaywas used to analysis the expression of MMP-9in serum on different time spot; Thetotal RNA was extracted in brain hippocampus of rats, RT-PCR assay was used todetect MMP-9gene transcription in hippocampus; extracted the nucleoprotein in ratbrain hippocampus organization, Western-blot was used to detect NF-κB activation inrats brain hippocampus.Result： The time and distance to reach the platform of the rat were measuredafter trained in Morris water maze test, compared with the first day, the time anddistance were shortened after the training, and the difference was statisticallysignificant (P <0.05); Compared with the group A, the time and distance to reach theplatform of group B and group C was significantly prolonged in the first day, but as time goes, The time and distance were gradually shorten, the change in time anddistance of in the group C were significant than in group B, the difference wasstatistically significant (P<0.05); Compared with group A, the MMP-9concentrationin serum of group B and group C increased significantly, but as time goes on, MMP-9expression in serum decreased gradually, MMP-9in serum was slightly higher ingroup C than in group B, the difference was statistically significant(P <0.05);compared with preoperative the first day, after the first day, the transcriptional level ofrat brain hippocampus of MMP-9in group B and group C were enhanced, but as timegoes on MMP-9gene transcription is gradually weakened, the difference wasstatistically significant (P<0.05);Compared with preoperative1d, NF-κB ofhippocampal organization activity was significantly increased in group B and group Cafter treatment, but as time goes on, activity of NF-κB was weakened gradually. thedifference was statistically significant (P <0.05),Conclusion1. Anesthesia and surgery can cause damage of the mice cognitive function, and theeffect of surgical is greater than anesthesia;2. The higher expression and concentration in serum and in hippocampus of MMP-9in rats are caused by anesthesia and surgery；The effection of surgery group isgreater than Anesthesia group in expression on MMP-9,and even lasts long;3. NF-κB may play an important role in the rat POCD process.