enkephalin

noun 0.898

preproenkephalin

noun 0.801

endorphin

noun 0.691

prodynorphin

noun 0.687

endothelin

noun 0.606

neuromedin

noun 0.589

ethylmorphine

noun 0.584

pethidine

noun 0.567

neuropeptide

noun 0.567

endophilin

noun 0.566

morphine

noun 0.565

endopeptidase

noun 0.565

meperidine

noun 0.553

diprenorphine

noun 0.547

normetanephrine

noun 0.544

endoproteinase

noun 0.540

anandamide

noun 0.534

midkine

noun 0.533

enamine

noun 0.528

methadone

noun 0.526

norepinephrine

noun 0.526

opioid

noun 0.522

encephalon

noun 0.517

opiate

noun 0.516

methacrolein

noun 0.515

diacetylmorphine

noun 0.513

neurokinin

noun 0.510

emetine

noun 0.509

mesenchyme

noun 0.508

phenethylamine

noun 0.506

enterocin

noun 0.505

methionine

noun 0.505

phenylethylamine

noun 0.503

peptide

noun 0.502

melatonin

noun 0.501