Irritation

Irritation

norepinephrine

75%

dynorphin a (1-17)

70%

dynorphin a (1-13)

70%

dynorphin b

70%

melatonin

65%

alpha-neoendorphin

60%

dopamine

55%

beta-neoendorphin

55%

beta-endorphin

50%

alpha-endorphin

50%

gamma-endorphin

50%

met-enkephalin

50%

leu-enkephalin

50%

serotonin

45%

anandamide

45%

oxytocin

40%

gaba

40%