Hybridisation Study of Neuronal Neuropeptides Expression in Models of Mandibular Denervation with or without Inflammation: Injury Dependant Neuropeptide Plasticity.

Unlabelled: Neuronal expression of neuropeptides is altered following peripheral tissue injury associated with inflammation or nerve injury. This results in neuropathic pain with or without neurogenic inflammation which is a major health problem regularly seen in trigeminal neuralgia. Activation of the trigeminal system results in the release of vasoactive neuropeptides substance P and Calcitonin Gene-related Peptide (CGRP) which contribute to nociception, pain and neurogenic inflammation in injured tissues.

Inflammation alters somatostatin mRNA expression in sensory neurons in the rat.

Proinflammatory neuropeptides, such as substance P and calcitonin gene-related peptide, are up-regulated in primary afferent neurons in acute and chronic inflammation. While these neuropeptides have been intensively studied, potentially anti-inflammatory and/or anti-nociceptive neuropeptides such as somatostatin (SS) have been less widely investigated. Endogenous somatostatin is thought to exert a tonic antinociceptive effect.

Inflammation alters cation chloride cotransporter expression in sensory neurons.

Cation chloride cotransporters have been proposed to play a role in the modulation of neuronal responses to gamma-aminobutyric acid (GABA). In conditions of neuronal damage, where neuronal excitability is increased, the expression of the KCC2 transporter is decreased. This is also seen in spinal cord in models of neuropathic pain.

Sensory neuropeptide mRNA up-regulation is bilateral in periodontitis in the rat: a possible neurogenic component to symmetrical periodontal disease.

Periodontal disease is a common multifactorial chronic inflammatory disease in humans. In inflammatory conditions that are known to be associated with changes in nociception, such as arthritis, the neuronal expression of the proinflammatory neuropeptides, substance P and calcitonin gene-related peptide is altered. In this study the expression of these neuropeptides' mRNAs has been studied in an inflammatory model that shows no behavioural evidence of altered nociception.