LIVER DIPEPTIDYL AMINOPEPTIDASE-IV HYDROLYZES SUBSTANCE-P
LIVER DIPEPTIDYL AMINOPEPTIDASE-IV HYDROLYZES SUBSTANCE-P
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DOI：
10.1016/0014-5793(78)81210-1
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发表时间：
1978-01-01
期刊：
影响因子：
3.5
通讯作者：
MENTLEIN, R
中科院分区：
文献类型：
--
作者：
HEYMANN, E;MENTLEIN, R
二肽基氨肽酶IV（EC 3.4. 14：）已从各种组织的微粒体组分中分离[1]，包括大鼠肝脏] 2]。该酶的活性通常用Gly-Pro-~-naphthylalide或类似的合成底物测定，其N-末端氨基酸旁有一个脯氨酸残基。据推测，这种酶可能参与胶原蛋白的周转[1]，但这对于膜结合的细胞内酶来说不太可能。到目前为止，还没有发现二肽氨基肽酶IV的生理底物。P物质是IL-11样的十一肽，它产生多种生理学效应，这些效应尚未完全了解[3，4]。它主要存在于神经系统和肠道中。除了对肠平滑肌和血管平滑肌的独特作用外，P物质还被讨论为神经递质。P物质的氨基酸序列（ArggPro-Lys-Pro-Gln-Gfn- Pile-Pfre-Gly-mu-Met. Nf~），表明它可能是一种很好的dipeltidyf ~ linopept ~ dase IV的底物.由于最近有报道说，肝脏对P物质有很强的抑制能力，我们想知道这种肽酶是否是造成这种效应的原因。
Dipeptidyl aminopeptidase IV (EC 3.4. 14:) has been isolated from the microsomal fractions of various tissues [1], including rat liver] 2], The activity of this enzyme has normally been determined with Gly-Pro-~-naphthyIal~ ide or similar synthetic substrates with a profine-residue next to the N-terminal amino acid. It has been assumed, that this enzyme might be involved in the turnover of collagen [l], but this is not very likely for a membrane-bound intracellular enzyme. So far, no physiological substrate has been found for dipeptidyl aminopeptidase IV. The Il~~ rltlone-like undecapeptide, substance P, produces a variety of pf~ ysiological effects which are not yet fully understood [3, 4]. it is mainly found in the nervous system and in the intestine. Besides its distinct effects on the smooth muscles of intestine and of blood vessels, substance P is also discussed as a neurotransmitter. The amino acid sequence of substance P (ArggPro-Lys--Pro-Gln-Gfn- Pile--Pfre-Gly-mu-Met.-Nf~~) suggests that it might be a good substrate for dipel~ tidyf~~ lllinopept~ dase IV. Since it has recently been reported [S] that fiver furs a higk capacity to inactivate substance P. we wondered whether this peptidase might be responsible for this effect.