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Table 2 Effects of CeA manipulation on pain-related outcomes in different pain models

From: The amygdala between sensation and affect: a role in pain

Pain type a Pain related outcome b Reference
  Nociceptive behavior Affective/emotional  
1. CeA lesion
  Naïve - Reduced morphine-induced, stress-induced and conditioned hypoalgesia   [55, 56, 69]
  Formalin - Reduced morphine-induced and conditioned hypoalgesia - Decreased pain-induced CPA [7073]
  Acetic acid   - Decreased pain-induced CPA [72]
2. Injection of muscimol
  Neuropathy - Reduced mechanical hyperalgesia - Decreased escape/avoidance [74]
3. Injection of NMDA antagonist
  Neuropathy   - Decreased pain-induced CPA [75]
4. Injection of group I mGluRs ligands
  Naïve - Agonist induced visceral and mechanical hypersensitivity   [76, 77]
- Antagonist reduced visceral sensitivity
  Formalin - Antagonist reduced mechanical hypersensitivity   [77]
  Arthritis - Antagonist reduced mechanical hypersensitivity - Antagonist decreased vocalizations [78]
  Neuropathy   - Agonist increased, and antagonist decreased, pain-induced CPA [75]
5. Injection of group III mGluRs agonists
  Naïve - Decreased mechanical sensitivity (mGluR7) - Decreased vocalizations and anxiety [79]
  Arthritis - Increased mechanical sensitivity (mGluR8) - Increased vocalizations and anxiety [79]
6. Injection of cholinergic agonists
  Naïve - Decreased thermal sensitivity, reduced jaw opening reflex - Decreased vocalizations [63, 65, 66]
7. Injection of noradrenergic α 2 ligands
  Naïve - Agonist induced mechanical and thermal hypoalgesia   [64, 80]
- Antagonist reduced stress-induced thermal hypoalgesia
  Acetic acid   - Agonist decreased pain-induced CPA [81]
8. Injection of noradrenergic β antagonists
  Acetic acid   - Decreased pain-induced CPA [81]
9. Injection of CGRP receptor ligands
  Naïve - CGRP decreased mechanical and thermal reflexes   [59]
  Naïve - CGRP increased mechanical reflexes - CGRP increased vocalizations [82]
  Arthritis - CGRP1 antagonist inhibited the enhanced reflex to mechanical stimulus - CGRP1 antagonist decreased vocalizations [83]
10. Injection of CRF receptor ligands
  Naïve - CRF decreased mechanical and thermal sensitivity   [58]
  Naïve - CRF increases mechanical sensitivity - CRF increased vocalizations [84]
  Arthritis - CRF1 antagonist reduced mechanical hypersensitivity - CRF1 antagonist decreased vocalizations and anxiety [85, 86]
11. Injection of oxytocin, vasopressin, neurotensin, galanin
  Naïve - Decreased mechanical and/or thermal sensitivity   [57, 6062]
12. Injection of opioid receptors ligands
  Naïve - Morphine and β-endorphin induced mechanical and thermal hypoalgesia - Morphine decreased vocalizations [47, 66]
13. Corticosterone implants
  Naïve - Sensitized visceromotor reflexes to colorectal and urinary bladder distension and to somatic mechanical sensitivity - Increased anxiety [8790]
14. BDNF gene deletion in the PB-CeA pathway
  Naïve - Decreased morphine-induced mechanical and thermal hypoalgesia   [68]
15. Intracellular effectors
  Naïve - ERK activator induced mechanical hypersensitivity   [30]
  Formalin - ERK activation inhibitor decreased mechanical hypersensitivity   [30, 31]
  Arthritis - ERK activation inhibitor and PKA inhibitor decreased mechanical hypersensitivity - ERK activation inhibitor and PKA inhibitor decreased vocalizations [91]
  1. aPain type. naive nociceptive testing on naive animals; formalin: intraplantar injection of diluted formalin in hindpaw; acetic: intraperitoneal injection of acetic acid; arthritis: intraarticular injection of kaolin-caragenean in knee; neuropathy: compression or ligation of sciatic nerve or spinal root.
  2. bPain related outcome. thermal sensitivity: latency of withdrawal or escape in tail-flick, hot-plate or Heargraves tests; mechanical sensitivity: latency or threshold to withdrawal in von Frey or Randall-Sellito tests; CPA: pain-induced conditioned place aversion; vocalizations: intensity/duration/threshold of vocalizations to electrical shock (naive) or mechanical compression of knee (naive, arthritis); anxiety: anxiety-like behavior in elevated plus maze test.