Aim:
To investigate and compare the levels of the beta-subunit of NGF (Beta-NGF) and middle molecular mass molecules (MMM) in the blood of patients with post-traumatic non-firearm and firearm neuropathies and plexopathies accompanied by chronic neuropathic pain.

Material and methods:
We examined 93 men aged 21-59 years with compression-ischemic (groupI - comparison), post-traumatic non-firearm (groupII) and firearm (groupIII) neuropathies and plexopathies with and without chronic neuropathic pain syndrome. Quantitative determination of Веtа-NGF in serum was performed by enzyme-linked immunosorbent assay. The content of MMM was determined by spectrophotometric method (fractions MMM238, MMM254, MMM260, MMM280). The following integral indices were calculated: peptide-nucleotide ratio, distribution coefficient, aromaticity coefficient.

Results:
We revealed an increased level of Beta-NGF in the blood serum of patients with post-traumatic firearm and non-firearm neuropathies and plexopathies accompanied by chronic neuropathic pain (Mann-WhitneyU-test,p=0.0077 and Mann-WhitneyU-test,p=0.04608, respectively). The level of the CR280/254 in patients of groupIII with post-traumatic firearm neuropathies and plexopathies at a statistically significant level depends on the presence of chronic neuropathic pain (Mann-WhitneyU-test,p=0.0113). The accumulation of biologically active molecules involved in the activation of compensatory, protective mechanisms in patients with post-traumatic firearm neuropathies and plexopathies accompanied by chronic neuropathic pain was established.

Conclusions:
The results confirm the existing data on the pathophysiological role of Beta-NGF and MMM in the development of chronic neuropathic pain and indicate the potential use of NGF as a therapeutic target, while the CR280/254 ratio may serve as a biomarker reflecting the accumulation of biologically active molecules associated with chronic neuropathic pain in patients with post-traumatic neuropathies and plexopathies.