Postsynaptic dorsal column pathway of the rat. II. Evidence against an important role in nociception

doi:10.1016/0006-8993(85)90044-7

Brain Research

Volume 326, Issue 2, 11 February 1985, Pages 347-356

https://doi.org/10.1016/0006-8993(85)90044-7 Get rights and content

Abstract

The response characteristics of neurons at the origin of the postsynaptic dorsal column (PSDC) pathway were determined in unanesthetized, decerebrated, spinalized rats. Sixty-four percent of PSDC neurons responded only to innocuous mechanical stimuli. Thirty-six percent responded to innocuous stimuli but were more powerfully activated by noxious pinch, Ninety-three percent of the tested PSDC neurons were not activated by any of several intensities of sustained, repeated noxious heating of their receptive fields. The failure of pinch-responssive PSDC cells to respond to thermal stimulation, even in sensitized skin, suggests that they do not receive a functionally significant input from C polymodal nociceptors, heat nociceptors, or mechanical-heat nociceptors. We conclude, therefore that the postsynaptic dorsal column pathway is not importantly involved in nociception in the rat.

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Citation Excerpt :
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Research reportPostsynaptic dorsal column pathway of the rat. II. Evidence against an important role in nociception

Abstract

Brain Research

Brain Research

Neuroscience

Neuroscience

Brain Research

Brain Research

Brain Research

The dorsal column system. I. Existence of long ascending postsynaptic fibres in the cat's fasciculus gracilis

Exp. Brain Res.

The dorsal column system. II. Functional properties and bulbar relay of the postsynaptic fibres of the cat's fasciculus gracilis

Exp. Brain Res.

The origin, distribution and synaptic relationships of substance P axons in rat spinal cord

J. comp. Neurol.

Three bulbospinal pathways from the rostral medulla of the cat: an autoradiographic study of pain modulating systems

J. comp. Neurol.

The cells of origin of the dorsal column postsynaptic projection in the lumbosacral enlargements of cats and monkeys

Somatosens. Res.

Response of cutaneous sensory units with unmyelinated fibers to noxious stimuli

J. Neurophysiol.

Receptive field organization and response properties of spinal neurones witt axons ascending the dorsal columns in the cat

J. Physiol. (Lond.)

Form and function of dorsal horn neurones with axons ascending the dorsal columns in cat

J. Physiol. (Lond.)

Morphology and organization of axon collaterals from afferent fibres of slowly adapting type I units in cat spinal cord

J. Physiol. (Lond.)

Sensitization of myelinated nociceptive afferents that innervate monkey hand

J. Neurophysiol.

Responses of spinocervical tract neurones to noxious stimulation of the skin

J. Physiol. (Lond.)

Peripheral neural correlates of behavior in monkey and human related to sensory-discriminative aspects of pain

Immunohistochemical studies using antibodies to leucine-enkephalin: initial observations on the nervous system of the rat

Neuroscience

The sensitization of high threshold mechanoreceptors with myelinated axons by repeated heating

J. Physiol. (Lond.)

Functional properties of primary afferent units probably related to pain mechanisms in primate glabrous skin

J. Neurophysiol.

Research report
Postsynaptic dorsal column pathway of the rat. II. Evidence against an important role in nociception