β-Endorphin, Met-enkephalin and corresponding opioid receptors within synovium of patients with joint trauma, osteoarthritis and rheumatoid arthritis

摘要: Objective: Intra-articularly applied opioid agonists or antagonists modulate pain after knee surgery and in chronic arthritis. Therefore, the expression of β-endorphin (END), Met-enkephalin (ENK), μ δ receptors (ORs) within synovium patients with joint trauma (JT), osteoarthritis (OA) rheumatoid arthritis (RA) were examined. Methods: Synovial samples subjected to double immunohistochemical analysis peptides immune cell markers, ORs neuronal markers calcitonin gene-related peptide (CGRP) tyrosine hydroxylase (TH). Results: END ENK expressed by macrophage-like (CD68 + ) fibroblast-like − cells synovial lining layers all disorders. In sublining layers, mostly granulocytes JT, macrophages/monocytes, lymphocytes plasma those OA RA. Overall, END- ENK-immunoreactive (IR) more abundant RA than JT. found on nerve fibres patients. OR-IR significantly μORs δORs coexpressed CGRP but not TH. Conclusions: Parallel severity inflammation, their sensory terminals are JT OA. These findings consistent notion that, prolonged enhanced peripheral nervous systems upregulate nerves expressing ligands counterbalance inflammation.