Descending Pain Pathway
The descending pain modulation is mainly mediated by monoaminergic pathways including descending projections mediated by dopamine norepinephrine and serotonin 78 79. The pathway that goes upward carrying sensory information from the body via the spinal cord towards the brain is defined as the ascending pathway whereas the nerves that goes downward from the brain to the reflex organs via the spinal cord is known as the descending pathway.
Pain is a vast subject and affects so many regions of an individuals body that we feel pain originating from numerous roots including cancer fibromyalgia neuropathic pain persistent post-surgical pain.
Descending pain pathway
. This chapter shows that although the detailed anatomy of the ascending pain pathways is still not fully understood projections that terminate in a large number of different areas of the brain associated with autonomic motor discriminative affective cognitive and motivational aspects of pain behaviour can be identified. We focus on discussing descending dopaminergic pathways in this review. Key nodes in the descending pain modulatory system.This analgesic effect arises from activation of descending pain-modulating pathways that project via the medulla to neurons in the dorsal horn that control the ascending information in the nociceptive system. Engagement of descending inhibition by the opioid analgesic morphine fulfils an important role in its pain-relieving properties while induction of analgesia by the adrenergic agonist clonidine reflects actions at alpha2-adrenoceptors alpha2-ARs in the DH normally recruited by descending pathways. Descending Pain Pathways Just as there are ascending pain pathways from the body to the brain there are also descending pain pathways communicating from the.
In turn the anterior cingulate cortex ACC is an origin of descending projection pathways that may directly terminate in the superficial DH and thus regulate nociceptive sensory transmission by explicit regulation of spinal neuronal activity 11 12. Descending pain pathway. The mode of action is not well understood but may be through activation of descending inhibitory.
Thalamic neurons descend to the midbrain. The central modulation of pain perception is the result of electrical or pharmacological stimulation of certain regions of the midbrain. Facilitatory pathways are the one which enhances pain perception where as inhibitory pathways suppresses pain perception.
Pain transmission can be modulated at a number of levels including the dorsal horn of the spinal cord and via descending inhibitory pathways. Where do I get my information from. In this review we discuss dopamine receptors dopaminergic systems in the brain and the role of descending dopaminergic pathways in the modulation of different types of pain.
The goal of this pathway is to allow the organism to function enough to respond to the pain source by reducing the pain signal through neuronal inhibition. Descending pain pathway Supraspinal or descending pain control pathways arises from a number of supraspinal sites. Most importantly descending dopaminergic pathways play an important role in pain modulation.
These pathways are monoaminergic utilising noradrenaline and serotonin as neurotransmitters. There they synapse on ascending pathways in the medulla and spinal cord and inhibit ascending nerve signals. This produces pain relief analgesia.
These receptors are called mu delta and kappa opioid receptors. Conditioned pain modulation CPM is the human counterpart of DNIC and requires a descending control also. Acupuncture is used for both acute and chronic pain.
These descending pathways are altered in neuropathy and the effects of excess serotonin may now become inhibitory through activation of spinal 5HT 7 receptors. These descending pathways originate in the somatosensory cortex which relays to the thalamus and the hypothalamus. PATHWAYS OF PAIN SENSATION The pathways of pain sensation are as follows Pathway from skin deeper tissues Pathway from face pain sensation is carried by trigeminal nerve Pathway from viscera pain sensation from thoracic abdominal viscera are transmitted by sympathetic nerves from oesophagus trachea pharynx by glossopharyngeal nerves Pathway.
Descending pathways project to the dorsal horn and inhibit pain pain transmission. Once the signal from the ascending pathway reaches the somatosensory cortex it triggers the descending pain modulation pathway. Descending Modulation of Pain Within the central nervous system there are three types of opioid receptors which regulate the neurotransmission of pain signals.
Deep and superficial pathways from the dorsal horn terminate in. The spinothalamic and spinoreticular tracts are important ascending pain pathways. Descending pain control pathways can be both facilitatory as well as inhibitory.
We describe anatomical structures and neurotransmitters of the descending inhibitory pain pathways that are activated in response to nociceptive pain and altered in response to sustained and persistent pain which leads to chronic pain in various pathological conditions.
Post a Comment for "Descending Pain Pathway"