Department of Biological Sciences, Idaho State University, Pocatello, Idaho, USA. 83209-8007
Anat Rec (Hoboken). 2010 Sep;293(9):1568-73. doi: 10.1002/ar.21197.
The muscle spindle has been well studied in mammals, birds, and some reptiles, but little is known about its structure and function in amphibians. Several physiological and behavioral studies in frogs and toads suggest that the submentalis muscle has an important role in jaw-tongue coordination during feeding through sensory feedback mechanisms. Evidence suggests this mechanism is generated through muscle spindles, or spindle-like structures. However, the presence of these has not been investigated. Using charged fluorescent molecules that are taken up by endocytosis at activated synapses, numerous muscle spindles were identified in the submentalis muscle of the marine toad, Bufo marinus. These were further verified with brightfield and differential interference contrast microscopy. The results provide anatomical evidence for muscle spindles in the submentalis muscle and suggest a mechanism for the submentalis muscle's role in jaw-tongue coordination in B. marinus.
肌梭在哺乳动物、鸟类和一些爬行动物中已有深入研究，但关于其在两栖动物中的结构和功能却知之甚少。一些针对青蛙和蟾蜍的生理学和行为学研究表明，下颌舌骨肌在摄食过程中通过感觉反馈机制在颌舌协调中发挥重要作用。有证据表明，这种机制是通过肌梭或类似肌梭的结构产生的。然而，这些结构的存在尚未得到研究。使用带电荷的荧光分子，这些分子通过被激活的突触处的胞吞作用被摄取，在海洋蟾蜍 Bufo marinus 的下颌舌骨肌中鉴定出许多肌梭。通过明场和微分干涉对比显微镜进一步验证了这些结果。这些结果为下颌舌骨肌中的肌梭提供了解剖学证据，并为肌梭在 B. marinus 颌舌协调中的作用提供了一种机制。
