Springate J, Hasan M, Rennick B, Fildes R, Feld L, Acara M
J Pharmacol Exp Ther. 1987 Feb;240(2):400-3.
The ability of several organic cations to inhibit differentially the renal excretion of two prototypical organic cations, tetraethylammonium (TEA) and N1-methylnicotinamide (NMN), was investigated using the Sperber technique in chickens. TEA and NMN excretion were inhibited by the following organic cations in order of decreasing potency: quinine, TEA and NMN. The respective competitive potency of these substances was related inversely to their maximum tubular transport rates (Tm). Regardless of inhibitor used (quinine, TEA or NMN), NMN excretion was always inhibited more easily than TEA excretion. In addition, TEA excretion was suppressed more easily than cimetidine excretion by the competitive inhibitor quinine. The Tm of cimetidine was determined to be less than the Tm of TEA, which in turn is less than that of NMN. These results indicate that the Tm of an organic cation is related inversely to its inhibitory potency and related directly to its susceptibility to inhibition, reflecting different affinities of organic cations for the same carrier-mediated transport system.
采用斯珀伯技术在鸡身上研究了几种有机阳离子对两种典型有机阳离子四乙铵（TEA）和N1-甲基烟酰胺（NMN）肾脏排泄的不同抑制能力。TEA和NMN的排泄被下列有机阳离子以效力递减的顺序抑制：奎宁、TEA和NMN。这些物质各自的竞争效力与其最大肾小管转运率（Tm）呈反比关系。无论使用何种抑制剂（奎宁、TEA或NMN），NMN的排泄总是比TEA的排泄更容易受到抑制。此外，竞争性抑制剂奎宁抑制TEA排泄比抑制西咪替丁排泄更容易。西咪替丁的Tm被确定小于TEA的Tm，而TEA的Tm又小于NMN的Tm。这些结果表明，有机阳离子的Tm与其抑制效力呈反比关系，与其被抑制的敏感性呈正比关系，反映了有机阳离子对同一载体介导转运系统的不同亲和力。
