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Maxadilan is a potent vasodilatory peptide present in the sali-vary glands of the sand fly. Maxadilan and M65, a deletion variation of maxadilan, are agonist- and antagonist-specific for the PAC1 receptor. In order to obtain the recombinant maxadilan and M65 efficiently by intein-mediated single col-umn purification, the genes encoding maxadilan and M65 were designed, synthesized and cloned into Escherichia coli expression vector pKYB. The recombinant maxadilan and M65 with homogeneity over 95% were released from the chitin-bound intein tag by β-mercaptoethanol. Intraperitoneal in-jection of the recombinant maxadilan caused an acute eleva-tion of plasma glucose, imitating pituitary adenylate cyclase-activating polypeptide (PACAP) 27, in NIH mice, while the VPACl-agonist and VPAC2-agonist had no significant ef-fects on the levels of plasma glucose. M65 alone had no effect on the plasma glucose, but blocked the glucose excursion caused by maxadilan by 12.7% and blocked the glucose ex-cursion caused by the PACAP 27 by 11.6%. The acute ef-fects of the recombinant maxadilan and M65 on the plasma glucose indicated that they had the characteristics as the agonist and antagonist for PAC1.