Abstract
The contractile responses to substance P (SP), neurokinin A (NKA), Tyr0-neurokinin B (Tyr-NKB), senktide (NK3 receptor selective agonist) and SP methyl ester (SPOMe, NK1 receptor selective agonist) were investigated in detrusor strips from guinea pigs. Except for senktide, all drugs induced a concentrationrelated contraction with the following rank order of potency: SPOMe>SP>NKA≥Tyr-NKB. After desensitization of NK1 receptors with SPOMe, the rank order of potency was NKA≥Tyr-NKB>SP>SPOMe. Both NK1 and NK2 receptors exist in the detrusor strip from guinea pigs.
