Chemokines, chemokine receptors and pain

Many patients suffer from neuropathic pain as a result of injury to the peripheral nervous system (e.g. post-herpetic neuralgia or diabetic neuropathy) or to the central nervous system (e.g. spinal cord injury or stroke). The most distinctive symptom of neuropathic pain is allodynia, whereby normally non-painful stimuli, such as light touch, become painful. Traditionally, inflammatory and neuropathic pain syndromes have been considered distinct entities; however, recent evidence belies this strict dichotomy. Nerve damage can stimulate macrophage infiltration and increase the number of activated T cells. Under these conditions, neuroinflammatory and immune responses contribute as much to the development and maintenance of pain as the initial damage itself. Recently, studies using animal models have shown that upregulation of chemokines is one of the mechanisms underlying the development and maintenance of chronic pain. Many patients suffer from neuropathic pain as a result of injury to the peripheral nervous system (e.g. post-herpetic neuralgia or diabetic neuropathy) or to the central nervous system (e.g. spinal cord injury or stroke). The most distinctive symptom of neuropathic pain is allodynia, whereby normally non-painful stimuli, such as light touch, become painful. Traditionally, inflammatory and neuropathic pain syndromes have been considered distinct entities; however, recent evidence belies this strict dichotomy. Nerve damage can stimulate macrophage infiltration and increase the number of activated T cells. Under these conditions, neuroinflammatory and immune responses contribute as much to the development and maintenance of pain as the initial damage itself. Recently, studies using animal models have shown that upregulation of chemokines is one of the mechanisms underlying the development and maintenance of chronic pain. sensation of pain, following injury or disease, in response to a previously non-noxious stimulus. An example of touch allodynia is pain from the touch of clothing. an increased response to a stimulus that is normally painful. It occurs following injury or disease and encompasses enhanced responses as well as reduced thresholds to a given noxious stimulus. any pain syndrome in which the predominating mechanism is a site of aberrant somatosensory processing in the peripheral or central nervous system. Neuropathic pain may occur following nerve injury (e.g. following crush, transection or compression of nerves, or following nerve degeneration produced by diseases, such as diabetes, or by viral infections). The underlying mechanisms include chronic alterations in peripheral as well as central components of pain pathways. the sensory component of pain (from Latin nocere, meaning to harm or damage). Nociception is the physiological sense for perception of physiological pain. nociceptors are a specific subset of peripheral sensory organs that respond to noxious stimuli.