Dynamics of the remodeling of neural connections in the superior cervical ganglion in rats after dosed compression of the preganglionic trunk.

The aim of the present work was to obtain a quantitative evaluation of post-traumatic regeneration of nerve cells in the superior cervical ganglion (SCG) by measuring the ratio of the number of neurons (N) in the ganglion to the number of preganglionic myelinated fibers (F) in the cervical sympathetic trunk (N/F). This was addressed using light and electron microscopy. Studies were performed using white male rats divided into three groups: intact (aged seven months), age controls (aged 19 months), and experimental - one year after compression of the sympathetic trunk at the base of the SCG performed at age seven months. N/F in intact rats was 1:210. With age, N/F changed to 1:173; the value one year after trauma was 1:745. These data led to the conclusion that normalization of the structure of the neural connections of the ganglion did not occur. The process of post-traumatic regeneration was incomplete and became chronic.