Management of chronic painful syndromes presents a tremendous challenge to the medical field as current pain management approaches with narcotics, such as morphine, carry adverse side effects such as sedation, constipation, tolerance and addiction. Therefore, a greater understanding of pathophysiological mechanisms that lead to a chronic pain state is needed for development of novel and effective therapies with minimal side effects. Recently, we demonstrated that when a conjugate of substance P (SP) and the ribosome-inactivating protein saporin (SAP) is infused into the spinal cord, the SP-SAP conjugate is specifically internalized and cytotoxic to lamina I spinal cord neurons that express the substance P receptor (SPR). This treatment leaves responses to mild noxious stimuli unchanged, but profoundly attenuates responses to highly noxious stimuli and to mechanical and thermal hyperalgesia. Using the intrathecal infusion of SP-SAP in the rat spinal cord as our model we propose: to investigate whether this treatment can alleviate inflammatory and/or neuropathic persistent pain states (Aim 1); to further define the rostral brain areas these neurons project to and the other receptors and neurotransmitters that are expressed by lamina I SPR-expressing neurons (Aim 2); to determine the functional role of neurons that express the SPR in nociceptive processing and hyperalgesia, and whether these SPR expressing neurons are functionally different from nociceptive neurons that do not express the SPR (Aim 3); and to determine whether reorganization of the spinal cord and dorsal root ganglia occurs following SP-SAP treatment and whether morphine is still effective in attenuating nociceptive responses (Aim 4). Information from these investigations will provide significant insight into the neurochemistry of spinal nociceptive signaling and whether SP-SAP treatment shows promise for developing non-opioid therapies to control chronic pain in humans.
Budai, Denes; Khasabov, Sergey G; Mantyh, Patrick W et al. (2007) NK-1 receptors modulate the excitability of ON cells in the rostral ventromedial medulla. J Neurophysiol 97:1388-95 |
Goblirsch, Michael; Lynch, Christine; Mathews, Wendy et al. (2005) Radiation treatment decreases bone cancer pain through direct effect on tumor cells. Radiat Res 164:400-8 |
Ghilardi, Joseph R; Rohrich, Heidi; Lindsay, Theodore H et al. (2005) Selective blockade of the capsaicin receptor TRPV1 attenuates bone cancer pain. J Neurosci 25:3126-31 |
Khasabov, Sergey G; Ghilardi, Joseph R; Mantyh, Patrick W et al. (2005) Spinal neurons that express NK-1 receptors modulate descending controls that project through the dorsolateral funiculus. J Neurophysiol 93:998-1006 |
Peters, Christopher M; Ghilardi, Joseph R; Keyser, Cathy P et al. (2005) Tumor-induced injury of primary afferent sensory nerve fibers in bone cancer pain. Exp Neurol 193:85-100 |
Luger, Nancy M; Mach, David B; Sevcik, Molly A et al. (2005) Bone cancer pain: from model to mechanism to therapy. J Pain Symptom Manage 29:S32-46 |
Mantyh, Patrick W (2004) A mechanism-based understanding of bone cancer pain. Novartis Found Symp 261:194-214; discussion 214-9, 256- |
Sevcik, Molly A; Luger, Nancy M; Mach, David B et al. (2004) Bone cancer pain: the effects of the bisphosphonate alendronate on pain, skeletal remodeling, tumor growth and tumor necrosis. Pain 111:169-80 |
Ghilardi, Joseph R; Svensson, Camilla I; Rogers, Scott D et al. (2004) Constitutive spinal cyclooxygenase-2 participates in the initiation of tissue injury-induced hyperalgesia. J Neurosci 24:2727-32 |
Peters, C M; Lindsay, T H; Pomonis, J D et al. (2004) Endothelin and the tumorigenic component of bone cancer pain. Neuroscience 126:1043-52 |
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