Human Disc Phospholipase A2 is Inflammatory

Immediate Pain Response to Interlaminar Lumbar Epidural Steroid Administration: Response Characteristics and Effects of Anesthetic Concentration

“…[13][14][15] Inflammatory mediators such as phospholipase A2, tumor necrosis factor-␣, interleukin-6, interleukin-8, and prostaglandin E2 have been found in degenerative and herniated disk material. [15][16][17][18][19][20][21] Increased intradiskal cytokines have been demonstrated in patients with diskogenic low back pain as well as sciatica. 20 Direct action of nucleus pulposus on the epidural space, nerve root, or DRG have demonstrated histologic changes (edema, hemorrhage, thrombus, nerve fiber injury, hyperemia) and nerve function changes (pain sensitivity, altered conduction velocity, spontaneous discharges, altered blood flow, increased endoneural pressure).…”

Outcomes of a prospective cohort study on peri-radicular infiltration for radicular pain in patients with lumbar disc herniation and spinal stenosis

“…In spinal stenosis, chronic mechanical compression and indirect vascular insufficiency lead to nerve root ischaemia and demyelination [31]. In contrast, experimental studies of the effect of LDH on the nerve root have shown that, in addition to mechanical compression, chemical irritation from the immunogenic substance of disc material may have a significant role in radiculopathy [7,20,21,22,24]. Corticosteroids that have both antiinflammatory [23] and local anaesthetic properties [9] may have much greater therapeutic value in LDH than in spinal stenosis.…”

Comparative immunohistochemical study of group II (synovial-type) and group IV (cytosolic) phospholipases A 2 in disc prolapse tissue

“…It has been suggested that very high PLA2 activity in pathological disc tissues may explain some of the nonmechanical influences in radiculopathy [7,20], but more recent studies [10,12] did not suggest higher levels of PLA2 activity in herniated discs in comparison with control disc tissues that were analyzed in parallel, employing identical assays. Miyahara et al [12] did, however, report higher PLA2 levels in disc tissues than in normal terminal ileal mucosa and in inflamed colonic mucosa.…”

“…So far only sPLA2 has been investigated in intervertebral disc tissue samples [7,10,12,20]. Some investigators suggested that herniated lumbar disc, especially in the case of sequestration, has a high PLA2 activity (sPLA2), which could be of pathophysiological importance in sciatica [17,20].…”