HrN-Tyr-Gly-Gly-Phe-Met-COO H N-lyr-Gly-GLy-Phe-Leu-COO Met-脑啡肽 Leu-脑啡肽 ys Cys yr LLe s Phe s GIn S GIn s Asn Asn Cys Cys Pro Pro Leu Arg Gly-NH2 Gly-NH2 件催产素 牛加压素Cys Tyr ILe Gln Asn Cys Pro Leu Gly NH2 S S 牛催产素 Cys Tyr Gln Asn Cys Pro S S Phe Arg Gly NH2 牛加压素 +H3N-Tyr-Gly-Gly-Phe-Met-COO- +H3N-Tyr-Gly-Gly-Phe-Leu-COO￾Met-脑啡肽 Leu-脑啡肽