Paul S, Volle D J, Currie J
Department of Pharmacology, University of Nebraska Medical Center, Omaha 68105.
Biochem J. 1988 Sep 1;254(2):613-5. doi: 10.1042/bj2540613.
Guinea pig vasoactive intestinal peptide (gpVIP) differs from other mammalian VIPs in four of its 28 amino acid residues. In the present study, the gpVIP displaced 125I-labelled pig VIP (pVIP) binding by rat lung membranes with 7.7-fold lower potency than pVIP. Degradation of gpVIP by rat lung membranes, assessed by radioimmunoassay and h.p.l.c., was 1.9-fold greater than that of pVIP. This difference in degradation of the two peptides was not large enough to account for the lower receptor-binding potency of gpVIP. The amino acid residues that distinguish pVIP from gpVIP are likely to contribute to the interaction of VIP with receptors and peptide hydrolases in lung membranes.
豚鼠血管活性肠肽（gpVIP）在其28个氨基酸残基中有4个与其他哺乳动物的VIP不同。在本研究中，gpVIP使大鼠肺膜上125I标记的猪VIP（pVIP）结合量减少，其效力比pVIP低7.7倍。通过放射免疫测定和高效液相色谱法评估，大鼠肺膜对gpVIP的降解比pVIP高1.9倍。这两种肽在降解上的差异不足以解释gpVIP较低的受体结合效力。区分pVIP和gpVIP的氨基酸残基可能有助于VIP与肺膜中受体和肽水解酶的相互作用。
