Impaired endocannabinoid signalling in the rostral ventromedial medulla underpins genotype-dependent hyper-responsivity to noxious stimuli

Impaired endocannabinoid signalling in the rostral ventromedial medulla underpins genotype-dependent hyper-responsivity to noxious stimuli.

Pain is both a sensory and an emotional experience, and is subject to modulation by a number of factors including genetic background modulating stress/affect. The Wistar-Kyoto (WKY) rat exhibits a stress-hyper-responsive and depressive-like phenotype and increased sensitivity to noxious stimuli, compared with other rat strains. Here, we show that this genotype-dependent hyperalgesia is associat...

Activation of rostral ventromedial medulla neurons by noxious stimulation of cutaneous and deep craniofacial tissues.

The rostral ventromedial medulla (RVM) projects to the medullary and spinal dorsal horns and is a major source of descending modulation of nociceptive transmission. Traditionally, neurons in the RVM are classified functionally as on, off, and neutral cells on the basis of responses to noxious cutaneous stimulation of the tail or hind paw. On cells facilitate nociceptive transmission, off cells ...

Activation of rostral ventromedial medulla neurons by noxious stimulation of cutaneous

Permanent lesion in rostral ventromedial medulla potentiates swim stress-induced analgesia in formalin test

Objective(s): There are many reports about the role of rostral ventromedial medulla (RVM) in modulating stress-induced analgesia (SIA). In the previous study we demonstrated that temporal inactivation of RVM by lidocaine potentiated stress-induced analgesia. In this study, we investigated the effect of permanent lesion of the RVM on SIA by using formalin test as a model of acute inflammatory pa...

Time-dependent descending facilitation from the rostral ventromedial medulla maintains, but does not initiate, neuropathic pain.

Although injury-induced afferent discharge declines significantly over time, experimental neuropathic pain persists unchanged for long periods. These observations suggest that processes that initiate experimental neuropathic pain may differ from those that maintain such pain. Here, the role of descending facilitation arising from developing plasticity in the rostral ventromedial medulla (RVM) i...