RESUMO
Objective To evaluate the effects of Ro20?1724 on cognitive dysfunction induced by repetitive ketamine anesthesia in immature rats. Methods Thirty?two Sprague?Dawley rats of both sex, aged 21 days, weighing 45-55 g, were randomly divided into 4 groups ( n=8 each ) using a random number table: control group ( group C ) , ketamine group ( group K ) , ketamine+Ro20?1724 group ( group K+R) , and ketamine+anhydrous alcohol group ( group K+A) . In K, K+R and K+E groups, 70 mg∕kg ketamine was intraperitoneally injected once a day for 7 consecutive days. The equal volume of normal saline was given instead in group C. Two days after the rats were fed a common diet, 0.5 mg∕kg Ro20?1724 and the equal volume of anhydrous alcohol were injected in K+R and K+E groups, respectively, and the equal volume of normal saline was given instead in K and C groups, once a day for 7 consecutive days. Morris water maze test was used to test cognitive function, and the escape latency and frequency of crossing the original platform were recorded. The rats were sacrificed after the end of behavior tests, and hippocampi were removed to detect the content of brain?derived neurotrophic factor ( BDNF) in CA1 region using enzyme?linked immunosorbent assay. Results Compared with group C, the escape latency was significantly prolonged on 1st-4th days in K and K+E groups, the escape latency was prolonged on 3rd-4th days in K+R group, and the frequency of crossing the original platform and content of BDNF in CA1 region were decreased in K, K+R and K+E groups. Compared with K group, the escape latency was significantly shortened, and the frequency of crossing the original platform was increased on 3rd-4th days, and the content of BDNF in CA1 region was increased in K+R group, and no significant changes were found in the parameters mentioned above in K+E group. Conclusion Ro20?1724 can improve cognitive dysfunction induced by repetitive ketamine anesthesia in immature rats, and enhanced production of BDNF is involved in the mechanism.