Foulks J G, Morishita L
Can J Physiol Pharmacol. 1984 Nov;62(11):1356-64. doi: 10.1139/y84-227.
Sufficiently high concentrations of cationic (n-alkyl trimethylammonium) or neutral (n-alkanols) amphipathic agents reduced the amplitude of maximum K contractures of frog toe muscles, an effect which was antagonized by reduced temperature, by the presence of perchlorate anions, or (to a lesser extent) by an increased concentration of divalent cations. Enhancement of the similar effect of tetracaine was prominent only with alkyl trimethylammonium compounds. Enhancement of the depressant effect of acidity (pH 5.0) was observed with octyl trimethylammonium and octanol but not with octanesulfonate or butanol. Partial restoration of potassium contractures in media lacking divalent cations was produced by octane- or nonane-sulfonate and by propanol but not by octyl trimethylammonium or octanol. The alkyl sulfonates differed from the other agents studied in producing tonic contractures at concentration which did not reduce maximum K-contracture tension. The alkyl sulfonates also differed from other amphipaths of similar size in their ability to elicit small repolarization-induced contractures in the absence of perchlorate, although this property also was shared by small alkanols. Sufficient concentrations of all amphipaths reduced the amplitude of repolarization-induced contractures in the presence of perchlorate. The intensity of the effects of these agents on contractile function usually was proportional to the size of their apolar group, and with ionic apmphipaths such effects were apparent only with compounds having hydrocarbon chains containing eight or more carbon atoms. These experiments indicate that hydrophobic interactions in the external lamina of the sarcolemma can influence the potential-dependent control of contractile function in skeletal muscle, presumably by effects on the conformational transitions of integral membrane proteins.(ABSTRACT TRUNCATED AT 250 WORDS)
足够高浓度的阳离子型（正烷基三甲基铵）或中性（正链烷醇）两亲性试剂会降低蛙趾肌最大钾挛缩的幅度，降低温度、存在高氯酸根阴离子或（在较小程度上）增加二价阳离子浓度可拮抗这一效应。仅在烷基三甲基铵化合物存在时，丁卡因的类似效应增强才很显著。在辛基三甲基铵和辛醇存在时可观察到酸度（pH 5.0）抑制效应增强，而在辛烷磺酸盐或丁醇存在时则未观察到。在缺乏二价阳离子的培养基中，辛烷磺酸盐或壬烷磺酸盐以及丙醇可使钾挛缩部分恢复，而辛基三甲基铵或辛醇则不能。烷基磺酸盐与其他所研究试剂的不同之处在于，在不降低最大钾挛缩张力的浓度下会产生强直性收缩。烷基磺酸盐与其他类似大小的两亲物的不同之处还在于，在不存在高氯酸根的情况下，它们能够引发小的复极化诱导收缩，不过小链烷醇也具有这一特性。在存在高氯酸根的情况下，所有两亲物的足够浓度都会降低复极化诱导收缩的幅度。这些试剂对收缩功能的影响强度通常与其非极性基团的大小成正比，对于离子型两亲物，只有具有含八个或更多碳原子烃链的化合物才会有明显效应。这些实验表明，肌膜外层的疏水相互作用可影响骨骼肌收缩功能的电位依赖性控制，推测是通过对整合膜蛋白构象转变的影响来实现的。（摘要截短至250字）
