Chinese Journal Of Clinical Anatomy ›› 2012, Vol. 30 ›› Issue (4): 431-434.

Previous Articles     Next Articles

Cervical vagus and sympathetic trunk and fiber components of external laryngeal nerve: comparative anatomy between human and dog

XU Shi-ye1, DONG Jian-ping1, SUN Shan-quan1, Kannaiyan Vijesh  Ramnarayan1,Joyeeta Sengupta2   

  1. 1.Department of Anatomy, Chongqing Medical University, Chongqing 400016, China;  2.Department of Molecular Biology and Cancer Research, Chongqing Medical University, Chongqing 400016, China
  • Received:2011-11-29 Published:2012-07-27

Abstract:

Objective    To compare the differences of cervical vagus and sympathetic trunks between human being and dog, and identify the fiber components of the dog external laryngeal nerve (ELN).   Methods   50 adult human cadavers fixed with formalin and 10 fresh dog cadavers were randomly used. The superior laryngeal nerve and its branches, superior cervical sympathetic ganglion (SCSG) and nodose ganglion (NG) were exposed. The communications between the cervical sympathetic trunk and the superior laryngeal nerve (SLN) were identified. The tissues from ELN and NG together with a branch from dog SCSG were taken for AchE activity analysis.    Results    In dog, the nodosum of vagus and the SCSG were completely or partially fused. In human being, the nodosum of vagus and SCSG separated, and in the most cases (86%) the SCSG connected with the ELN. The AchE staining demonstrated the presence of three different types of fibers in dog ELN: AchE-positive myelinated fibers, AchE-negative myelinated fibers and AchE-positive unmyelinated fibers.    Conclusions    ELN is looped in shape and innervates the thyroid gland. ELN is a mixed nerve carrying somato-motor, post-ganglionic sympathetic and a few somato-sensory fibers.

Key words: Superior cervical sympathetic ganglion(SCSG, Superior laryngeal nerve (SLN), External laryngeal nerve (ELN), Nodose ganglion (NG), Nerve fiber component, Human being, Dog

CLC Number: