Synovial fluid: a key role in arthritis pain?

Normally, the synovial fluid provides a smooth movement. Now British scientists have proved that the "Gelenkschmiere" of osteoarthritis patients in the nerve cells causes, apparently, a pain response that is similar to that of chili peppers.

The scientists are nerve cells that transmit signals from the knee had brought with synovial fluid from osteoarthritis patients as well as deceased with no known joint disease, and the activity of the nerve is recorded. They found that the nerves were more excitable when they were exposed to the synovial fluid of osteoarthritis patients. As they report in the journal Rheumatology, was the strength of the response is comparable with that observed in the case of a stimulus with chili peppers. The scientists suspect that substances, which are released from inflammatory cells in the synovial fluid, leading to the pain response.

Osteoarthritis is the most common joint disorder and causes pain, stiffness, swelling, and a sensitivity of the joints. It usually occurs later in life and is regarded as a degenerative disease, the pain caused by damage to and erosion of bone and cartilage are produced. In recent years, however, has shown that inflammation significantly contribute to the pain of the patients. Inflammatory cells release substances into the synovial fluid, the consistency of change, and, as we know now, in contact with the sensory nerve cells to the feeling of pain generating.

Dr. Ewan St. John Smith of the Department of pharmacology at the University of Cambridge explains possible applications: "In the future this System can be used to identify the specific components of the synovial fluid that cause pain, and to test whether and how a drug for arthritic pain will help." ZOU