BoNT/A complex absorption from the stomach and the small intestine. The pylorus was ligated, and mice were injected with HA+ complex or HA− complex. Neurotoxin complex introduced into the intestine is represented by the open bars, and complex introduced into the stomach is represented by the hatched bars. (A) HA+ complex with hemagglutinins. (B) HA− complex without hemagglutinins. HA+ complex (equivalent to 1 μg of neurotoxin/animal): stomach, n = 9; intestine, n = 9. HA− complex (equivalent to 1 μg neurotoxin/animal): stomach, n = 10; intestine, n = 12. Results are means and SEM.