尽管多数蛋白与内源性肽的同源性较小,但它们都是通过相同的受体发挥作用。虽这些物质与受体亲和性下降2～3个位数,但口服后仍有作用。蛋白除可派生受体配体外,还可派生酶抑制物、抗菌肽、吸收调节肽等。类鸦片肽最初从食品蛋白衍生的生理活性肽是Brantl等人从酪蛋白陈分离的类鸦片肽β-ca-somorphin(YPFPGPI)。β-casomorphin具有延缓食物通过肠管速度和促进胰岛素分泌的作用。此肽在脑室内投用时有镇痛作用,而口服时没有镇痛作用。日本京都大学农学部的吉川 Although most proteins have less homology to endogenous peptides, they all function through the same receptor. Although these substances and receptor affinity decreased by 2 to 3 digits, but still have an effect after oral administration. In addition to the protein receptor ligand can be derived, but also derived from enzyme inhibitors, antimicrobial peptides, absorption regulating peptides. Analogs of opioid peptides Physiologically active peptides originally derived from food proteins are the opioid peptide β-ca-somorphin (YPFPGPI) isolated from casein by Brantl et al. β-casomorphin has the effect of slowing the rate of food passage through the intestine and promoting insulin secretion. This peptide in the intraventricular analgesic effect when administered, but no analgesic effect of oral administration. Yoshikawa, Faculty of Agriculture, Kyoto University, Japan