Researchers from Japan's Osaka University have made an important leap in our understanding of how chronic pain conditions develop. In a study published online on July 25, 2019 in the Journal of Neuroscience, the team explains how a protein previously implicated in neuron growth and cell adhesion is also critical for the development of pain sensitization (see image below). The article is titled “Increased Expression of Fibronectin Leucine-Rich Transmembrane Protein 3 in the Dorsal Root Ganglion Induces Neuropathic Pain in Rats.” Neuropathic pain is a chronic condition arising from previous nerve injury or certain diseases, including diabetes, cancer, and multiple sclerosis. Affected patients often display hypersensitivity to normally non-painful stimuli such as touch or repetitive movement, with pain commonly manifesting as shooting burning sensations, numbness, or pins and needles. In many cases, the pain cannot be relieved with analgesics. In humans, the spinal cord dorsal horn acts as a sorting station for pain stimuli. Signals coming in from peripheral areas of the body are processed and then transmitted via secondary neurons to the brain. Importantly, this is a key region in the development of neuropathic pain; studies have linked the condition to abnormal neuronal excitability in the spinal cord dorsal horn. However, what causes these neurons to become overly excited remains a mystery. FLRT3 (fibronectin leucine-rich transmembrane protein-3) is a protein commonly found in both embryonic and adult nervous systems. And while researchers don't know exactly what role it plays in adult tissues, FLRT3 has been implicated in synapse formation and cell adhesion in the developing brain.Login Or Register To Read Full Story