Blankenship J E, Rock M K, Hill J
J Neurobiol. 1977 Nov;8(6):549-68. doi: 10.1002/neu.480080605.
The properties of the penis retractor muscle of Aplysia have been studied using intracellular, sucrose gap and tension recording. The fibers are of the invertebrate smooth muscle type and exhibit slow contractions which occur spontaneously or in response to stretch in isolated preparations. Individual muscle fibers are innervated by excitatory and inhibitory axons. A variety of sizes of excitatory and inhibitory junctional potentials can be recorded from them. The innervation is probably diffuse and functionally polyneuronal. The fibers are electrically coupled, permeable to potassium and chloride at rest, and exhibit no overshooting active responses. The muscle shows graded responses of depolarization and contraction proportional to strength of nerve stimulation. Facilitation and depression of junctional potentials are seen with various frequencies of nerve stimulation. Post-tetanic potentiation occurs with nerve stimulation at frequencies from 2 to 50 Hz and is suppressed in the presence of increased extracellular calcium concentrations.
已使用细胞内、蔗糖间隙和张力记录法对海兔阴茎牵缩肌的特性进行了研究。这些纤维属于无脊椎动物平滑肌类型，表现出缓慢收缩，在离体标本中，这种收缩可自发发生或对拉伸产生反应。单个肌纤维由兴奋性和抑制性轴突支配。从它们身上可记录到各种大小的兴奋性和抑制性接头电位。这种神经支配可能是弥散性的，且在功能上是多神经元的。这些纤维通过电耦合，静息时对钾离子和氯离子通透，且不表现出超射性主动反应。该肌肉表现出与神经刺激强度成比例的去极化和收缩的分级反应。在不同频率的神经刺激下可观察到接头电位的易化和抑制。强直后增强在2至50赫兹的神经刺激频率下出现，且在细胞外钙浓度升高时受到抑制。
