Thomas G, Mostaghim R, Ramwell P W
Biochem Biophys Res Commun. 1986 Dec 15;141(2):446-51. doi: 10.1016/s0006-291x(86)80193-0.
The vascular endothelium appears obligatory for the expression of the vasodilating property of most polypeptides. A number of polypeptides were studied on the rat aortic ring preparation which was pre-contracted with phenylephrine and only basic polypeptides containing one or more arginine residues elicited relaxation which was endothelium dependent. These peptides included melittin and poly-L-Arg. The basic polypeptide poly-L-Lys also elicited endothelium dependent relaxation, but to a lesser extent than arginine containing polypeptides. Two basic polypeptides, apamin and mastoparan do not promote endothelium dependent relaxation. The former contains arginine between disulfide bonds and in the latter arginine is absent. Basic amino acids and dipeptides which contain arginine, and also polyamines did not elicit relaxation even at high concentrations (10(-3) M). The relaxation elicited by melittin, poly-L-Arg and poly-L-Lys was inhibited by ETYA, NDGA, p-bromophenacyl bromide and not by indomethacin. Methylene blue, an inhibitor of soluble guanylate cyclase, also abolished the relaxation. We suggest that arginine containing peptides may relax vascular smooth muscle by acting directly on the vascular smooth muscle (eg: atriopeptins) and/or or by eliciting release of a relaxing factor(s) from the endothelium.
血管内皮似乎是大多数多肽血管舒张特性表达所必需的。在预先用去氧肾上腺素预收缩的大鼠主动脉环标本上研究了多种多肽，只有含有一个或多个精氨酸残基的碱性多肽能引起内皮依赖性舒张。这些肽包括蜂毒肽和聚-L-精氨酸。碱性多肽聚-L-赖氨酸也能引起内皮依赖性舒张，但程度小于含精氨酸的多肽。两种碱性多肽，蜂毒明肽和马斯托帕兰不促进内皮依赖性舒张。前者在二硫键之间含有精氨酸，而后者不含精氨酸。含精氨酸的碱性氨基酸和二肽以及多胺即使在高浓度（10(-3)M）下也不引起舒张。蜂毒肽、聚-L-精氨酸和聚-L-赖氨酸引起的舒张被ETYA、NDGA、对溴苯甲酰溴抑制，而不被消炎痛抑制。可溶性鸟苷酸环化酶抑制剂亚甲蓝也消除了舒张作用。我们认为含精氨酸的肽可能通过直接作用于血管平滑肌（如心房肽）和/或通过引起内皮释放舒张因子来舒张血管平滑肌。
