Uchida D, Tatsuno I, Tanaka T, Hirai A, Saito Y, Moro O, Tajima M
Second Department of Internal Medicine, Chiba University School of Medicine, Japan.
Ann N Y Acad Sci. 1998 Dec 11;865:253-8. doi: 10.1111/j.1749-6632.1998.tb11185.x.
Maxadilan is a potent vasodilator peptide isolated from salivary glands extracts of the hematophagous sand fly. Recently, it was demonstrated that maxadilan binds to PACAP receptor type 1 in mammals, although maxadilan has no significant amino acid sequence homology with PACAP. In the present study, we demonstrated that maxadilan is a specific agonist of PACAP type 1 receptor (PACAP/VIP receptor 1; PVR1) as determined by the binding assay of [125I]PACAP27 and cAMP accumulation using CHO cells stably expressing PVR1, VIP1 receptor (PVR2), and VIP2 receptor (PVR3), and that the deleted peptide (#25-41) of maxadilan (termed as M65) is a specific antagonist of PVR1. In addition, maxadilan shares the binding sites for PACAP and stimulates cAMP in cultured rat cortical neurons. VIP stimulates cAMP accumulation probably through the binding to PVR1 since M65 blocks the VIP-induced cAMP accumulation in cultured rat cortical neurons.
马克西迪兰是一种从吸血白蛉唾液腺提取物中分离出的强效血管舒张肽。最近有研究表明，马克西迪兰可与哺乳动物的1型垂体腺苷酸环化酶激活肽（PACAP）受体结合，尽管马克西迪兰与PACAP没有明显的氨基酸序列同源性。在本研究中，我们通过使用稳定表达PVR1、VIP1受体（PVR2）和VIP2受体（PVR3）的CHO细胞进行[125I]PACAP27结合试验和环磷酸腺苷（cAMP）积累试验，证明马克西迪兰是1型PACAP受体（PACAP/血管活性肠肽受体1；PVR1）的特异性激动剂，并且马克西迪兰的缺失肽（#25 - 41）（称为M65）是PVR1的特异性拮抗剂。此外，马克西迪兰与PACAP共享结合位点，并能刺激培养的大鼠皮质神经元中的cAMP产生。血管活性肠肽（VIP）可能通过与PVR1结合来刺激cAMP积累，因为M65可阻断VIP诱导的培养大鼠皮质神经元中的cAMP积累。
