Prostaglandin release from lumbar disc and facet joint tissue

The authors measured prostaglandin (PG) and leukotriene (LT) release from human disc and lumbar facet joint tissues. High levels of phospholipase A2 (PLA2) have been measured in the human disc. PLA2 releases fatty acids from lipid membranes. These can be converted to PG and LT, which are potent inflammatory mediators and supposed to be involved in lumbar diseases. The tissues were obtained during surgery and incubated in Tyrode's solution. PG and LT release was measured radioimmunologically from the supernatant. Disc (4 ng/g wet weight), cartilage (21 ng/g wet weight), and bone (14 ng/g wet weight) released PGs but no LTs. Because PG release from sequestrated disc is rather low, the inflammatory effect might be more because of immunologic reactions.