A morphological-histochemical study of neurodegenerative and regenerative processes in flexor and extensor collaterals of the sciatic nerve after crushing in the presence of PRP-1

A comparative morphological and histochemical study of the dynamics of de- and regenerative processes in the damaged sciatic nerve (SN) area was conducted in rats at different time points after crushing in the presence of proline-rich peptide (PRP-1). We measured the activity of Ca 2+ -dependent acid phosphatase (AP). At the fifth day after SN crushing on the site of injury, we observed changes in the directions of nerve fibers and disruption of their structure, in particular, swelling of Schwann hollow tubes. Later, we found proliferation of cells of the endoneurium and Schwann cells in the extensor bundle ( N. peroneus communis ), which promoted recovery of nerve fibers and was accompanied by appearance of the maximum activity AP. We also showed partial recovery of the flexor bundle ( N. Gastrocnemius ). At 17 days after the trauma, as a result of successful regeneration of the damaged nerve, we observed the recovery of nerve fibers and their structures, which confirms the neuroprotective characteristics of PRP-1