Lembeck F, Griesbacher T
Department of Experimental and Clinical Pharmacology, University of Graz, Austria.
J Cardiovasc Pharmacol. 1990;15 Suppl 6:S75-7.
Peptide analogs of bradykinin (BK) containing unusual amino acids are potent antagonists of the actions of BK in various smooth muscle preparations. Apparent pA2 values above 7.0 could be demonstrated for Lys-Lys-[Hyp3, Thi5.8, D-Phe7]-BK (B4310) in the rat uterus and the rat duodenum. Actions of BK that are related to its possible role in inflammation could be antagonized in a specific and dose-dependent manner by B4310. Stimulation by BK of C fiber afferent neurons was investigated in the rabbit ear reflex preparation and in the isolated rabbit iris sphincter muscle. In both preparations, B4310 caused a parallel shift of the dose-response curves to BK. In the latter case, a pA2 value was established that agrees well with the values found on smooth muscles. However, the short duration of action of the antagonists suggested a rapid inactivation by peptidases.
含有异常氨基酸的缓激肽（BK）肽类似物是BK在各种平滑肌制剂中作用的强效拮抗剂。在大鼠子宫和大鼠十二指肠中，Lys-Lys-[Hyp3, Thi5.8, D-Phe7]-BK（B4310）的表观pA2值可证明高于7.0。B4310可以以特异性和剂量依赖性方式拮抗与BK在炎症中可能作用相关的作用。在兔耳反射制剂和离体兔虹膜括约肌中研究了BK对C纤维传入神经元的刺激作用。在这两种制剂中，B4310导致剂量-反应曲线向BK平行移动。在后一种情况下，确定的pA2值与在平滑肌上发现的值非常吻合。然而，拮抗剂作用持续时间短表明其被肽酶快速灭活。
