Nervous system nerve cord

Peripheral nervous system Nerve tissues lying outside the brain and spinal cord, functions include the transmittal of sensory information such as touch, heat, cold, and pain, and the motor impulses for limb movement. 

Ecstasy also stimulates the sympathetic nervous system (nerves located outside the brain and spinal cord), causing increases in heart rate and blood pressure. 

Neurotoxicity Cells of the central nervous system, CNS (brain and spinal cord) and the peripheral nervous system (nerves outside the CNS) Neuronopathies (neuron injury) Axonopathies (axon injury) Demyelination (loss of axon insulation) Interference with neurotransmission... 

Reports of neurological adverse effects after tetanus immunization have appeared (8). The most common reported complication is a polyneuropathy. In the majority of cases the onset occurred within 14 days of the last injection, and ranged in severity from a single nerve palsy to profound sensorimotor involvement of the nervous system, including cord and cortex. Recovery was usually complete (eight of 10 patients with onset at less than 14 days after injection) but three patients with onset at more than 14 days from injection had only partial recovery. 

The number of so-called nodes of Ranvier (Figure 6.29) determines the transmission speed within the nerve pathway which can be measured by means of myography . Table 6.2 lists a number of transmission speeds in various nerve pathways. In the central nervous system (spinal cord and... 

Damage of the central nervous system (nerves of spinal cord) can be caused by disease or trauma and often results in paralysis, which at present can not be cured. Every year, more than 11,000 individuals sustain spinal injury in the USA. These are mostly young men, median age 26. Of the quarter of a million people living in the USA after spinal cord injury, nearly half have irreversible loss of neurologic function below the level of injury (with either lower limbs or all four limbs paralyzed). (Madigan et al., 2009). It is known, that in Europe it is comparable number but complete data is not available. The aim of a lot researches is to pave the way for reversing this loss of neurologic functions, which is still perceived as irreversible . 

As a neurotransmitter in the sensory nervous system, high levels of substance P are found in the dorsal horn of the spinal cord as well as in peripheral sensory nerve terminals. However, substance P also plays a significant role as a neuromodulator in the central, sympathetic, and enteric nervous system. NKA and NKB are also localized selectively in the CNS. 

The human body has more than 600 muscles. The body s movement is performed by muscle contractions, which are stimulated by the nervous system. This system links muscle tissue to the spinal cord and brain. The network of nerve cells which carries the brain s signals directs the flow of muscular energy. Most muscular activity occurs beyond the range of the conscious mind. The body, working through the neuromuscular network, manages... 

The neuraxis is the rostrocaudal extension of the nervous system including forebrain, midbrain, brainstem, spinal cord, and peripheral nerves. 

The neuropathological analysis of HIV-associated neuropathies should include the different central and peripheral nervous system structures associated with sensory pathways, including spinal cord, dorsal root ganglia (DRG), peripheral nerve, and cutaneous nerve fibers (Pardo et al. 2001) (Fig. 4.1). The majority of studies have focused on the evaluation of the peripheral nerve, often from sural nerve biopsies and the DRG. Few studies have examined the pathology of sensory pathways in the... 

Association of Pain, neuropathic pain is defined as pain initiated or caused by a primary lesion, dysfunction in the nervous system". Neuropathy can be divided broadly into peripheral and central neuropathic pain, depending on whether the primary lesion or dysfunction is situated in the peripheral or central nervous system. In the periphery, neuropathic pain can result from disease or inflammatory states that affect peripheral nerves (e.g. diabetes mellitus, herpes zoster, HIV) or alternatively due to neuroma formation (amputation, nerve transection), nerve compression (e.g. tumours, entrapment) or other injuries (e.g. nerve crush, trauma). Central pain syndromes, on the other hand, result from alterations in different regions of the brain or the spinal cord. Examples include tumour or trauma affecting particular CNS structures (e.g. brainstem and thalamus) or spinal cord injury. Both the symptoms and origins of neuropathic pain are extremely diverse. Due to this variability, neuropathic pain syndromes are often difficult to treat. Some of the clinical symptoms associated with this condition include spontaneous pain, tactile allodynia (touch-evoked pain), hyperalgesia (enhanced responses to a painful stimulus) and sensory deficits. 

Another very important site for drug delivery is the central nervous system (CNS). The blood-brain barrier presents a formidable barrier to the effective delivery of most agents to the brain. Interesting work is now advancing in such areas as direct convective delivery of macromolecules (and presumably in the future macromolecular drug carriers) to the spinal cord [238] and even to peripheral nerves [239]. For the interested reader, the delivery of therapeutic molecules into the CNS has also been recently comprehensively reviewed... 

The central nervous system (CNS) consists of the brain and spinal cord. The peripheral nervous system (PNS) consists of 12 pairs of cranial nerves that arise from the brainstem and 31 pairs of spinal nerves arising from the spinal cord. These peripheral nerves carry information between the CNS and the tissues of the body. The PNS consists of two divisions ... 

At this point, it is important to note that a nerve is defined as a bundle of neuronal axons some are afferent and some are efferent. A nerve does not consist of entire neurons, only their axons. Furthermore, nerves are found only in the peripheral nervous system. Bundles of neurons with similar functions located within the CNS are referred to as tracts. Therefore, technically speaking, no nerves are within the brain or the spinal cord. 

The cell bodies of visceral motor neurons are found in the lateral horn. The axons of these neurons form efferent nerve fibers of the autonomic nervous system (ANS). The ANS innervates cardiac muscle, smooth muscle and glands (see Chapter 9). The axons of these neurons exit the spinal cord by way of the ventral root. 

By immunohistochemistry, a- and p-synucleins are concentrated in nerve terminals, with little staining of somata and dendrites. Ultrastructurally, they are found in close proximity to synaptic vesicles. In contrast,y-synuclein is present throughout nerve cells in many brain regions. In rat, a-synuclein is most abundant throughout telencephalon and diencephalon, with lower levels in more caudal regions. P-Synuclein is distributed fairly evenly throughout the central nervous system, whereas y-synuclein is most abundant in midbrain, pons and spinal cord, with much lower levels in forebrain areas. 

Nervous System The entire nerve apparatus composed of the brain, spinal cord, nerves and ganglia. [NIH]... 

The spinal cord is the major route of input and output for the centrai nervous system. It is covered by the meninges and sits within the vertebral column. There are 31 pairs of spinai nerves, exiting at the dorsal and ventral roots of the spinal cord. The spinal cord is divided into four levels (superior to inferior) cervical, thoracic, lumbar, and sacral. A cross section of the spinal cord shows a butterflyshaped core of gray matter (neuronal soma), and an outer surrounding area of white matter (axon tracts). 

The nervous system consists of two main units the central nervous system (CNS), which includes the brain and the spinal cord and the peripheral nervous system (PNS), which includes the body s system of nerves that control the muscles (motor function), the senses (the sensory nerves), and which are involved in other critical control functions. The individual units of the nervous system are the nerve cells, called neurons. Nenrons are a nniqne type of cell becanse they have the capacity to transmit electrical messages aronnd the body. Messages pass from one nenron to the next in a strnctnre called a synapse. Electric impnlses moving along a branch of the nenron called the axon reach the synapse (a space between nenrons) and canse the release of certain chemicals called neurotransmitters, one of which, acetylcholine, we described earlier in the chapter. These chemicals migrate to a nnit of the next nenron called the dendrites, where their presence canses the bnild-np of an electrical impnlse in the second nenron. 

The central nervous system includes the brain and the spinal cord. We shall refer to it as the CNS. The peripheral nervous system, PNS, is composed of nerves, bundles of individual cells called neurons, which connect the CNS to the rest of the body. If we make a very rough analogy to a bicycle wheel, then the CNS is the hub and the PNS is the spokes. When the bike tire hits the road, force is generated at the hub and is transmitted by the spokes. 

Central Nervous System (CNS). The human nervous system is an integrated communication network that sends and receives information throughout the body. This network is divided into two main divisions central nervous system (CNS) and peripheral nervous system (PNS). The CNS is the command center of this network and is made up of the brain and spinal cord. The PNS is the interface of the nervous system with the rest of the body and the external environment. It is comprised of nerve fibers and small clusters of nerve cells known as ganglia. 

In addition to the physiological process of autoinhibition, another mechanism of presynaptic inhibition has been identified in the peripheral nervous system, although its precise relevance to the brain is unclear. In the dorsal horn of the spinal cord, for example, the axon terminal of a local neuron makes axo-axonal contact with a primary afferent excitatory input, which leads to a reduction in the neurotransmitter released. This is due to the local neuron partly depolarizing the nerve terminal, so that when the axon potential arrives, the change induced is diminished, thereby leading to a smaller quantity of transmitter being released. In the brain, it is possible that GABA can cause presynaptic inhibition in this way. 

Exposure to disulfoton can result in inhibition of cholinesterase activity in blood and at nerve synapses of muscles, secretory organs, and nervous tissue in the brain and spinal cord. Central nervous system signs and symptoms include anxiety, restlessness, depression of respiratory and circulatory centers, ataxia, convulsions, and coma. 

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