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Parabrachial Nucleus (PBn) Pituitary Adenylate Cyclase Activating Polypeptide (PACAP) Signaling in the Amygdala: Implication for the Sensory and Behavioral Effects of Pain

Overview
Specialties Neurology
Pharmacology
Date 2014 Jul 8
PMID 24998751
Citations 67
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Abstract

The intricate relationships that associate pain, stress responses and emotional behavior have been well established. Acute stressful situations can decrease nociceptive sensations and conversely, chronic pain can enhance other pain experiences and heighten the emotional and behavioral consequences of stress. Accordingly, chronic pain is comorbid with a number of behavioral disorders including depression, anxiety abnormalities and associated stress-related disorders including post traumatic stress disorder (PTSD). The central nucleus of the amygdala (CeA) represents a convergence of pathways for pain, stress and emotion, and we have identified pituitary adenylate cyclase activating polypeptide (PACAP) immunoreactivity in fiber elements in the lateral capsular division of the CeA (CeLC). The PACAP staining patterns colocalized in part with those for calcitonin gene related peptide (CGRP); anterograde fiber tracing and excitotoxic lesion studies demonstrated that the CeLC PACAP/CGRP immunoreactivities represented sensory fiber projections from the lateral parabrachial nucleus (LPBn) along the spino-parabrachioamygdaloid tract. The same PBn PACAP/CGRP fiber system also projected to the BNST. As in the BNST, CeA PACAP signaling increased anxiety-like behaviors accompanied by weight loss and decreased feeding. But in addition to heightened anxiety-like responses, CeA PACAP signaling also altered nociception as reflected by decreased latency and threshold responses in thermal and mechanical sensitivity tests, respectively. From PACAP expression in major pain pathways, the current observations are novel and suggest that CeA PACAP nociceptive signaling and resulting neuroplasticity via the spino-parabrachioamygdaloid tract may represent mechanisms that associate chronic pain with sensory hypersensitivity, fear memory consolidation and severe behavioral disorders.

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References
1.
Ikeda R, Takahashi Y, Inoue K, Kato F . NMDA receptor-independent synaptic plasticity in the central amygdala in the rat model of neuropathic pain. Pain. 2006; 127(1-2):161-72. DOI: 10.1016/j.pain.2006.09.003. View

2.
Hammack S, Cheung J, Rhodes K, Schutz K, Falls W, Braas K . Chronic stress increases pituitary adenylate cyclase-activating peptide (PACAP) and brain-derived neurotrophic factor (BDNF) mRNA expression in the bed nucleus of the stria terminalis (BNST): roles for PACAP in anxiety-like behavior. Psychoneuroendocrinology. 2009; 34(6):833-43. PMC: 2705919. DOI: 10.1016/j.psyneuen.2008.12.013. View

3.
Robinson D, Wei F, Wang G, Li P, Kim S, Vogt S . Oxytocin mediates stress-induced analgesia in adult mice. J Physiol. 2002; 540(Pt 2):593-606. PMC: 2290243. DOI: 10.1113/jphysiol.2001.013492. View

4.
Pettersson L, Heine T, Verge V, Sundler F, Danielsen N . PACAP mRNA is expressed in rat spinal cord neurons. J Comp Neurol. 2004; 471(1):85-96. DOI: 10.1002/cne.20015. View

5.
Veinante P, Yalcin I, Barrot M . The amygdala between sensation and affect: a role in pain. J Mol Psychiatry. 2014; 1(1):9. PMC: 4223879. DOI: 10.1186/2049-9256-1-9. View