Parallel “Pain” Pathways Arise from Subpopulations of Primary Afferent Nociceptor

@article{Braz2005ParallelP,
  title={Parallel “Pain” Pathways Arise from Subpopulations of Primary Afferent Nociceptor},
  author={Jo{\~a}o M. Braz and Mohammed A. Nassar and John N. Wood and Allan I. Basbaum},
  journal={Neuron},
  year={2005},
  volume={47},
  pages={787-793}
}

Figures from this paper

Innocuous, Not Noxious, Input Activates PKCγ Interneurons of the Spinal Dorsal Horn via Myelinated Afferent Fibers
TLDR
It is established that PKCγ interneurons are activated by myelinated afferents that respond to innocuous stimuli, which suggests that injury-induced mechanical allodynia is transmitted through a circuit that involves PKCα interneURons and non-nociceptive, VGLUT1-expressing myelination primary afferentS.
Genetically expressed transneuronal tracer reveals direct and indirect serotonergic descending control circuits
TLDR
The results indicate that 5HT neurons influence “pain” processing at the spinal cord level both directly and indirectly via feedforward connections with multiple non‐5HT descending control pathways.
Dorsal horn circuitry
TLDR
These findings provide new insights into the pathophysiology of the manifestations of neuropathic pain, including spontaneous pain, hyperalgesia, and mechanical allodynia, as well as neuropathic itch.
Non-peptidergic primary afferents are presynaptic to neurokinin-1 receptor immunoreactive lamina I projection neurons in rat spinal cord
TLDR
These results indicate the presence of direct innervation by non-peptidergic nociceptive afferents of lamina I projection neurons expressing NK-1r, and better understand the role of these connections in physiological conditions and chronic pain states.
The role of the lateral spinal nucleus in nociception
TLDR
The extent of involvement of the L SN in nociception is less than previously thought, but with projections to the hypothalamus, it could be postulated that the LSN functions as an integrative nucleus for autonomic and homeostatic functions, and related motivational and affective responses to autonomic function.
Pain Pathways and Descending Inhibitory Pathways Implicated in Nociceptive Modulation
TLDR
The purpose of the present review is to summarize the current knowledge of the structure of the pain system, including both the ascending and the descending components.
...
...

References

SHOWING 1-10 OF 37 REFERENCES
Peptide- and non-peptide-containing unmyelinated primary afferents: the parallel processing of nociceptive information.
  • S. Hunt, J. Rossi
  • Biology
    Philosophical transactions of the Royal Society of London. Series B, Biological sciences
  • 1985
TLDR
It is suggested that peptide- and non-peptide-containing afferents are two distinct C fibre pathways innervating similar peripheral structures and conveying similar information, but to different areas within the dorsal horn.
Neurokinin 1 receptor expression by neurons in laminae I, III and IV of the rat spinal dorsal horn that project to the brainstem
TLDR
It is demonstrated that dorsal horn neurons which express the neurokinin 1 receptor contribute to several ascending pathways that are thought to be important in pain mechanisms.
PROPRIOSPINAL PATHWAYS AND THEIR SYNAPSES.
Projection Neurons in Lamina I of Rat Spinal Cord with the Neurokinin 1 Receptor Are Selectively Innervated by Substance P-Containing Afferents and Respond to Noxious Stimulation
TLDR
It is concluded that presence or absence of the NK1 receptor is a better indicator of function than morphology for lamina I projection neurons in the rat, and for both substance P innervation and c-Fos expression there were no significant differences among different morphological types of NK1 receptors.
Tackling Pain at the Source: New Ideas about Nociceptors
Neurons in the dorsal column white matter of the spinal cord: complex neuropil in an unexpected location.
TLDR
A network of neurons located along the midline of the dorsal column (DC) white matter are described, indicating that the DC neurons are under tonic inhibitory control and can respond to neurotransmitters that circulate in the cerebrospinal fluid.
Nociceptive responses in the neostriatum and globus pallidus of the anesthetized rat.
TLDR
A large proportion of somatosensory neurons within the neostriatum and globus pallidus of anesthetized rats receive nociceptive information, and individual stimulus-response functions of nOCiceptive neurons were best fit by a negatively accelerating (logarithmic) curves.
The spino(trigemino)pontoamygdaloid pathway: electrophysiological evidence for an involvement in pain processes.
TLDR
Neurons recorded in the parabrachial (PB) area, located in the dorsolateral region of the pons, in the anesthetized rat exhibited a clear capacity to encode thermal stimuli in the noxious range.
Transneuronal Labeling of a Nociceptive Pathway, the Spino-(Trigemino-)Parabrachio-Amygdaloid, in the Rat
TLDR
Results demonstrate that nociceptive input to the amygdala is relayed from neurons in lamina I through the elPB, and proposes that this modular arrangement of lamina II and II neurons may provide the basis for spinal processing of peripheral input toThe amygdala.
...
...