Structure-Activity Relationships of Neuromedin U.I. Contractile Activity of Dog Neuromedin U-Related Peptides on Isolated Chicken Crop Smooth Muscle.
作者:Naoki SAKURA、Katsuro KUROSAWA、Tadashi HASHIMOTO
DOI:10.1248/cpb.43.1148
日期:——
Synthetic dog neuromedin U-25(d-NMU-25), U-8(d-NMU-8) and their fragments were examined for contractile activity on chicken crop smooth muscle preparation. The relative activities of d-NMU-25, d-NMU-25 (15-25)-NH2 and d-NMU-8 to porcine neuromedin U-8 (p-NMU-8) were 1.69, 2.54 and 5.78, respectively. High activity of d-NMU-8 may be attributable to the N-terminal pGlu residue, which provides resistance to aminopeptidases. Various NMU-8 analogs, having various amino acids, Nα-acetylated amino acids, D-amino acids, or simple organic acids at position 1, were synthesized and evaluated for contractile activity. None of the substitutions caused a significant decrease of the biological activity. Modification at the N-terminal to give aminopeptidase resistance produced analogs with increased contractile activity, presumably because they were not degraded by soluble enzymes released into the bioassay fluid from isolated chicken crop tissue.
研究了合成的狗神经生长素 U-25(d-NMU-25)、U-8(d-NMU-8)及其片段在鸡嗉囊平滑肌制备上的收缩活性。d-NMU-25、d-NMU-25 (15-25)-NH2 和 d-NMU-8 与猪神经生长因 U-8(p-NMU-8)的相对活性分别为 1.69、2.54 和 5.78。d-NMU-8 的高活性可能归因于 N 端 pGlu 残基对氨基肽酶的抗性。我们合成了各种 NMU-8 类似物,它们在第 1 位具有各种氨基酸、Nα-乙酰化氨基酸、D-氨基酸或简单的有机酸,并对其收缩活性进行了评估。所有的取代都不会导致生物活性的显著降低。在 N 端进行修饰以获得抗氨肽酶能力的类似物具有更高的收缩活性,这可能是因为它们不会被从分离的鸡嗉囊组织释放到生物测定液中的可溶性酶降解。