Ion Channels and Osteoarthritic Pain: Potential for Novel Analgesics
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Abstract
Osteoarthritis (OA) is a debilitating chronic condition widely prevalent in ageing populations. Because the pathology of the disease includes cartilage erosion and joint remodelling, OA patients experience a great deal of pain. Despite numerous studies, details of OA are frequently inseparable from other types of chronic pain, and its causes are unknown. In most circumstances in OA, the cartilage lacks afferent innervation, although other joint tissues contain nociceptive neurones. In addition to physical joint damage, there is a strong element of joint inflammation. Genetic studies have identified several associations between ion channels and OA pain, including NaV1.7, P2X7, and TRPV1, but several other channels have also been implicated. Many ion channels involved with OA pain are common to those seen in inflammatory pain. This review considers causes of OA pain and discusses three possible pain-reducing strategies involving ion channel modulation: chondroprotection, innate afferent nerve inhibition, and inhibition of inflammatory hyperalgesia. Future targets for OA pain analgesia could involve a number of ion channels.
Keywords
Osteoarthritis Chondrocytes Cannabinoids Ion channels Dorsal root ganglia Chronic pain GabapentinNotes
Acknowledgments
This research has received partial funding from the European Union Seventh Framework Programme (FP7/2007-2013) under grant agreement n° 305815.
Compliance with Ethics Guidelines
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Conflict of Interest
The authors do not have any conflicts of interest.
Human and Animal Rights and Informed Consent
This article does not contain any studies with human or animal subjects performed by any of the authors.
References
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