Figure 4. Influence of nefiracetam on task recall and NCAM polysialylation state after propofol-induced retrograde amnesia. In Panel A, recall is compared between control animals and those treated with propofol alone (150 mg/kg at 3-h post-training) and in combination with nefiracetam (9 mg/kg at 1 h pretraining). Nefiracetam alone had no effect on recall. The frequency of polysialylated neurons in these groups is shown in Panel B. Treatment with propofol significantly attenuated both parameters (P < 0.05; Mann-Whitney U-test and Student's t test for panel A and B, respectively) as indicated by [section]. Similarly, both were significantly preserved by administration of nefiracetam with propofol compared with animals that received propofol alone as indicated with an asterisk. Values represent the median and interquartile range and the mean +/- SEM in panels A and B, respectively (n = 6). C = control; P = propofol; P + N = propofol and nefiracetam; N = nefiracetam.