Inhibition of AChE activity in adult Schistosoma japonicum protein preparations or intact worms. a
SjAChE activity in the tegument extract was significantly higher (about 10-fold; P < 0.0001) than in the carcasses of adult worms. The IC50 (50 % inhibition) of BW284c51 on SjAChE in the tegumental protein extract of adult worms is indicated as dotted lines at a concentration of 16 μM. b The sensitivity of SjAChE in the tegument and carcasses, isolated from cultured male and female worms in the presence of 200 μM BW284c51, were different. At the same concentration of tegument protein, paired worms had higher SjAChE activity than single-sex worms with male worms (P = 0.0175) having a higher SjAChE activity than females (P < 0.0001). After treatment with BW284c51, SjAChE enzyme activity in tegument protein extracts of paired worms, male worms and female worms decreased by 59 %, 22 % and 50 %, respectively (P < 0.0001). Compared with the tegumental protein extract, there was much less SjAChE activity in the carcass protein extract, with a relatively higher activity in males. Error bars represent the standard error of the mean (SEM). These experiments were performed three times (n = 3). Relative activity (%) = 100 × (sample fluorescence – negative fluorescence)/(positive–negative fluorescence). *P ≤ 0.05, **P ≤ 0.001, ***P ≤ 0.0001