title: Detection of a long acting endogenous opioid in blood and small intestine.
mesh_terms: D000818:Animals; D001681:Biological Assay; D001921:Brain / Q000378:metabolism; D002855:Chromatography, Thin Layer; D004796:Clinical Enzyme Tests; D004558:Electric Stimulation; D004723:Endorphins; D006168:Guinea Pigs; D007082:Ileum / Q000032:analysis*; D008970:Molecular Weight; D009132:Muscles / Q000502:physiology; D009294:Narcotics / Q000097:blood / Q000302:isolation & purification; D009928:Organ Specificity; D010455:Peptides / Q000302:isolation & purification; D051381:Rats; D011957:Receptors, Opioid / Q000378:metabolism; D013045:Species Specificity
chemical_list: D004723:Endorphins; D009294:Narcotics; D010455:Peptides; D011957:Receptors, Opioid