Harris J B, Pollard S, Tesseraux I
Br J Pharmacol. 1985 Sep;86(1):275-86. doi: 10.1111/j.1476-5381.1985.tb09459.x.
Some effects of the sea anemone toxin, ATX-II, on vertebrate skeletal muscle have been described. At a concentration of 1 X 10(-7)-1 X 10(-6)M, ATX-II caused a sodium-dependent depolarization of the muscle fibres of the rat soleus and extensor digitorum longus, of the mouse soleus and extensor digitorum longus and of the chicken posterior latissimus dorsi. The muscle fibres of the frog sartorius were insensitive to the toxin. Action potentials generated by direct stimulation were prolonged by ATX-II, but the degree of prolongation was variable. Chicken posterior latissimus dorsi muscle fibres were most sensitive in this regard, and mouse extensor digitorum longus were least sensitive. Both denervated and immature muscle fibres were more sensitive to ATX-II than mature innervated muscle fibres. The sensitivity to ATX-II declined rapidly as muscle fibres matured. In some muscles, the prolongation of the action potential was enhanced by repetitive stimulation, but not by the passive depolarization or hyperpolarization of the muscle fibres. The actions of ATX-II could be reversed by washing in all but the innervated soleus of the mature rat.
海葵毒素ATX-II对脊椎动物骨骼肌的一些作用已被描述。在浓度为1×10⁻⁷ - 1×10⁻⁶M时，ATX-II引起大鼠比目鱼肌和趾长伸肌、小鼠比目鱼肌和趾长伸肌以及鸡背阔肌的肌纤维发生钠依赖性去极化。青蛙缝匠肌的肌纤维对该毒素不敏感。直接刺激产生的动作电位被ATX-II延长，但延长程度各不相同。在这方面，鸡背阔肌的肌纤维最敏感，而小鼠趾长伸肌最不敏感。去神经和未成熟的肌纤维比成熟的有神经支配的肌纤维对ATX-II更敏感。随着肌纤维成熟，对ATX-II的敏感性迅速下降。在一些肌肉中，动作电位的延长通过重复刺激增强，但不是通过肌纤维的被动去极化或超极化。除了成熟大鼠有神经支配的比目鱼肌外，通过冲洗可逆转ATX-II的作用。
