Günzel D, Rathmayer W
Fakultät für Biologie, Universität Konstanz, FRG.
J Muscle Res Cell Motil. 1994 Oct;15(5):535-46. doi: 10.1007/BF00121159.
The 'catch-like' effect, a hysteresis phenomenon in arthropod skeletal muscle contraction thought to be related to the catch of molluscan smooth muscle, was investigated in the closer muscle of the crab Eriphia spinifrons. Several parameters were varied to determine their influence on the catch-like effect. These parameters were (1) the frequency of repetitive stimulation of the slow excitatory neuron, (2) additional stimulation of the inhibitory neuron, (3) the amount of stretch applied to the muscle and (4) the stiffness of the mechano-electrical transducer. The results show that the catch-like effect is not related to the catch of molluscan smooth muscle but rather to the 'residual force enhancement' or 'creep' phenomenon described for vertebrate muscle. A hypothesis for residual force enhancement implies that the increase in force is caused by non-uniformity of sarcomere lengths along the muscle fibre. Based on this hypothesis and the actual force-length relationship of the crab muscle studied, calculations were carried out to determine, if the observed catch-like effect can be explained by such a model. The calculations corroborate the experimental evidence. The catch-like effect of arthropod muscles can thus be explained by the same mechanism responsible for residual force enhancement and creep in vertebrate muscle. A physiological relevance of the catch-like effect in arthropod muscle is inferred.
在多刺艾氏蟹的闭壳肌中，研究了“似捕捉”效应，这是节肢动物骨骼肌收缩中的一种滞后现象，被认为与软体动物平滑肌的捕捉现象有关。改变了几个参数以确定它们对似捕捉效应的影响。这些参数包括：（1）慢兴奋性神经元的重复刺激频率；（2）抑制性神经元的额外刺激；（3）施加于肌肉的拉伸量；（4）机电换能器的刚度。结果表明，似捕捉效应与软体动物平滑肌的捕捉现象无关，而是与脊椎动物肌肉中描述的“残余力增强”或“蠕变”现象有关。残余力增强的一种假说认为，力的增加是由沿肌纤维的肌节长度不均匀所致。基于这一假说以及所研究的蟹肌肉的实际力-长度关系，进行了计算，以确定观察到的似捕捉效应是否可以用这样一个模型来解释。计算结果证实了实验证据。因此，节肢动物肌肉的似捕捉效应可以用与脊椎动物肌肉中残余力增强和蠕变相同的机制来解释。推断了节肢动物肌肉中似捕捉效应的生理相关性。
