|
Dorsolateral Pontine Reticular Formation
The dorsolateral pontine reticular formation contains noradrenergic pain-inhibiting neurons which project to inhibitory interneurons of the substantia gelatinosa of the posterior grey column in the spinal cord. It thus complements the classical serotonergic-opioid peptide descending pain-inhibiting system: whereas the serotonergic-opioid peptide pathway ultimately pre-synaptically inhibits first-order nociceptive group C neurons, the DLPRF inhibits - by way of presumably GABAergic inhibitory interneurons - the second-order neurons of the ascending pain pathway. The DLPRF pathway is not affected by opioid agonists or antagonists. It is also involved in REM sleep. See also * Raphespinal tract - the canonical descending pain-inhibiting pathway which the DLPRF functionally complements. * Reticular formation The reticular formation is a set of interconnected nuclei that are located throughout the brainstem. It is not anatomically well defined, because it includes neurons l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Noradrenergic
Norepinephrine (NE), also called noradrenaline (NA) or noradrenalin, is an organic chemical in the catecholamine family that functions in the brain and body as both a hormone and neurotransmitter. The name "noradrenaline" (from Latin '' ad'', "near", and ''ren'', "kidney") is more commonly used in the United Kingdom, whereas "norepinephrine" (from Ancient Greek ἐπῐ́ (''epí''), "upon", and νεφρός (''nephrós''), "kidney") is usually preferred in the United States. "Norepinephrine" is also the international nonproprietary name given to the drug. Regardless of which name is used for the substance itself, parts of the body that produce or are affected by it are referred to as noradrenergic. The general function of norepinephrine is to mobilize the brain and body for action. Norepinephrine release is lowest during sleep, rises during wakefulness, and reaches much higher levels during situations of stress or danger, in the so-called fight-or-flight response. In the b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Interneuron
Interneurons (also called internuncial neurons, relay neurons, association neurons, connector neurons, intermediate neurons or local circuit neurons) are neurons that connect two brain regions, i.e. not direct motor neurons or sensory neurons. Interneurons are the central nodes of neural circuits, enabling communication between sensory or motor neurons and the central nervous system (CNS). They play vital roles in reflexes, neuronal oscillations, and neurogenesis in the adult mammalian brain. Interneurons can be further broken down into two groups: local interneurons and relay interneurons. Local interneurons have short axons and form circuits with nearby neurons to analyze small pieces of information. Relay interneurons have long axons and connect circuits of neurons in one region of the brain with those in other regions. However, interneurons are generally considered to operate mainly within local brain areas. The interaction between interneurons allow the brain to perform ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Substantia Gelatinosa Of Rolando
The apex of the posterior grey column, one of the three grey columns of the spinal cord, is capped by a V-shaped or crescentic mass of translucent, gelatinous neuroglia, termed the substantia gelatinosa of Rolando (or SGR) (or gelatinous substance of posterior horn of spinal cord), which contains both neuroglia cells, and small nerve cells. The gelatinous appearance is due to a very low concentration of myelinated fibers. It extends the entire length of the spinal cord and into the medulla oblongata where it becomes the spinal nucleus of the trigeminal nerve. It is named after Luigi Rolando. It corresponds to Rexed lamina II. Structure The SGR, or lamina II, is composed of an outer lamina II and an inner lamina II. In rodents, the inner lamina II is divided into a dorsal and ventral inner lamina II. The distinction between these laminae lies in the areas of the spinal cord that send information to and from the laminae (input and output projections). The cell types ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Posterior Grey Column
The posterior grey column (posterior cornu, dorsal horn, spinal dorsal horn, posterior horn, sensory horn) of the spinal cord is one of the three grey columns of the spinal cord. It receives several types of sensory information from the body, including fine touch, proprioception, and vibration. This information is sent from receptors of the skin, bones, and joints through sensory neurons whose cell bodies lie in the dorsal root ganglion. Anatomy The posterior grey column is subdivided into six layers termed Rexed laminae I-VI * Marginal nucleus of spinal cord (lamina I) * Substantia gelatinosa of Rolando (lamina II) * Nucleus proprius (laminae III, IV) * Spinal lamina V, the neck of the posterior horn * Spinal lamina VI, the base of the posterior horn. The other four Rexed laminae are located in the other two grey columns in the spinal cord. Additional images File:Gray687.png, Section of the medulla oblongata through the lower part of the decussation of the pyramids ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spinal Cord
The spinal cord is a long, thin, tubular structure made up of nervous tissue, which extends from the medulla oblongata in the brainstem to the lumbar region of the vertebral column (backbone). The backbone encloses the central canal of the spinal cord, which contains cerebrospinal fluid. The brain and spinal cord together make up the central nervous system (CNS). In humans, the spinal cord begins at the occipital bone, passing through the foramen magnum and then enters the spinal canal at the beginning of the cervical vertebrae. The spinal cord extends down to between the first and second lumbar vertebrae, where it ends. The enclosing bony vertebral column protects the relatively shorter spinal cord. It is around long in adult men and around long in adult women. The diameter of the spinal cord ranges from in the cervical and lumbar regions to in the thoracic area. The spinal cord functions primarily in the transmission of nerve signals from the motor cortex to the b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Raphespinal Tract
The raphespinal tract is a descending spinal cord tract located in the medulla oblongata. It consists of two tracts an anterior raphespinal tract, and a lateral raphespinal tract that mainly descend in the lateral funiculus. Fibers descend in the ventral portion of the lateral funiculus, mainly bilaterally to terminate in laminae I, II, and IV. The tract emerges from three of the raphe nuclei, the magnus, obscurus, and pallidus. The fibers of the raphespinal tract are mainly serotonergic. When raphe nuclei are stimulated they release serotonin which modulates the transmission of pain. Pathways Pain pathways converging upon the raphe nuclei to modulate pain via the raphespinal tract include: ** Laminae I and V of spinal cord→ spinomesencephalic tract → periaqueductal gray → nucleus raphe magnus → ** Laminae I and V of spinal cord → spinomesencephalic tract → mesencephalon raphe nuclei → ** Nociceptive group C first-order nerve fiber → interneurons of lami ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Group C Nerve Fiber
Group C nerve fibers are one of three classes of nerve fiber in the central nervous system (CNS) and peripheral nervous system (PNS). The C group fibers are unmyelinated and have a small diameter and low conduction velocity, whereas Groups A and B are myelinated. Group C fibers include postganglionic fibers in the autonomic nervous system (ANS), and nerve fibers at the dorsal roots (IV fiber). These fibers carry sensory information. Damage or injury to nerve fibers causes neuropathic pain. Capsaicin activates C fibre vanilloid receptors, giving chili peppers a hot sensation. Structure and anatomy Location C fibers are one class of nerve fiber found in the nerves of the somatic sensory system. They are afferent fibers, conveying input signals from the periphery to the central nervous system. Structure C fibers are unmyelinated unlike most other fibers in the nervous system. This lack of myelination is the cause of their slow conduction velocity, which is on t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
GABAergic
In molecular biology and physiology, something is GABAergic or GABAnergic if it pertains to or affects the neurotransmitter GABA. For example, a synapse is GABAergic if it uses GABA as its neurotransmitter, and a GABAergic neuron produces GABA. A substance is GABAergic if it produces its effects via interactions with the GABA system, such as by stimulating or blocking neurotransmission. A GABAergic or GABAnergic agent is any chemical that modifies the effects of GABA in the body or brain. Some different classes of GABAergic drugs include agonists, antagonists, modulators, reuptake inhibitors and enzymes. See also * GABA reuptake inhibitor * Adenosinergic * Adrenergic * Cannabinoidergic * Cholinergic * Dopaminergic * Glycinergic * Histaminergic * Melatonergic * Monoaminergic * Opioidergic * Serotonergic Serotonergic () or serotoninergic () means "pertaining to or affecting serotonin". Serotonin is a neurotransmitter. A synapse In the nervous system, a synapse ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rapid Eye Movement Sleep
Rapid eye movement sleep (REM sleep or REMS) is a unique phase of sleep in mammals and birds, characterized by random rapid movement of the eyes, accompanied by low muscle tone throughout the body, and the propensity of the sleeper to dream vividly. The REM phase is also known as paradoxical sleep (PS) and sometimes desynchronized sleep or dreamy sleep, because of physiological similarities to waking states including rapid, low-voltage desynchronized brain waves. Electrical and chemical activity regulating this phase seems to originate in the brain stem, and is characterized most notably by an abundance of the neurotransmitter acetylcholine, combined with a nearly complete absence of monoamine neurotransmitters histamine, serotonin and norepinephrine. Experiences of REM sleep are not transferred to permanent memory due to absence of norepinephrine. REM sleep is physiologically different from the other phases of sleep, which are collectively referred to as non-REM sleep (NRE ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reticular Formation
The reticular formation is a set of interconnected nuclei that are located throughout the brainstem. It is not anatomically well defined, because it includes neurons located in different parts of the brain. The neurons of the reticular formation make up a complex set of networks in the core of the brainstem that extend from the upper part of the midbrain to the lower part of the medulla oblongata. The reticular formation includes ascending pathways to the cortex in the ascending reticular activating system (ARAS) and descending pathways to the spinal cord via the reticulospinal tracts. Neurons of the reticular formation, particularly those of the ascending reticular activating system, play a crucial role in maintaining behavioral arousal and consciousness. The overall functions of the reticular formation are modulatory and premotor, involving somatic motor control, cardiovascular control, pain modulation, sleep and consciousness, and habituation. The modulatory functions are pri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
