SPECIFICITY OF INITIAL SYNAPTIC CONTACTS MADE ON GUINEA-PIG SUPERIOR CERVICAL GANGLION CELLS DURING REGENERATION OF THE CERVICAL SYMPATHETIC TRUNK

This study investigates how nerve cells in the superior cervical ganglion of guinea pigs reconnect after nerve damage. The researchers examined whether the connections are random at first or if they are specific from the beginning. The study found that even in the early stages of nerve regeneration, the connections formed are largely appropriate. This suggests that the nerve cells have a way of finding their correct partners from the start, rather than making random connections and then correcting them later. The experiments involved stimulating different nerve roots and observing the responses in the animal's body, as well as recording electrical activity from individual nerve cells in the ganglion.

• 1
  Appropriate, but weak, end-organ responses were elicited by stimulation of the first and fourth thoracic ventral roots (Ti and T4) 15-30 days after freezing the cervical sympathetic trunk.
• 2
  Synaptic contacts are first re-established 8-11 days after freezing the preganglionic nerve.
• 3
  Patterns of segmental innervation recorded intracellularly during the early stages of regeneration were similar to, but more restricted than normal.