Nerve peripheral

Under the microscope perineurium and endoneurium are thickened. Typically (Dereux 1963) but not always (Veltema and Verjaal 1961) the appearance resembles that of hypertrophic polyneuritis, type Dejerine-Sottas (Edstrom et al. 1959). Microscopic lesions vary in intensity in different sections, and are most marked where the tissue appears edematous on gross examination. Here, the axis cylinders are diminished in number and are separated by an amorphous material which stains metachromatic with cresyl violet, toluidin blue and PAS (Cammermeyer 1956). The accumulation of serous fluid which apparently is responsible for the swelling (Gordon and Hudson 1959, Alexander 1966) may be limited to peripheral bundles, and the metachromatic material may become less or may 

Cammermeyer 1956, Edstrom et al. 1959) (see figures 5, 6 and 7 b, c). Occasionally these onion shells may be formed by polynucleated cells, and sometimes they 

The blood vessels of nerves appear moderately sclerotic. The subcapsular space is frequently widened by an exudate containing protein and fat. In summary, nerve changes are similar to those occurring with Wallerian degeneration, associated with variable degrees of connective tissue hyperplasia. Histochemical studies show that there is lipid deposition as droplets or in the form of phagocytized material (Cammermeyer 1956, Alexander 1966) along the whole course of peripheral nerves. 

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Lidocaine hydrochloride [73-78-9] (Xylocaine), is the most versatile local anesthetic agent because of its moderate potency and duration of action, rapid onset, topical activity, and low toxicity. Its main indications are for infiltration, peripheral nerve blocks, extradural anesthesia, and in spinal anesthesia where a duration of 30 to 60 min is desirable. Because of its vasodilator activity, addition of the vasoconstrictor, epinephrine, increases the duration of action of Hdocaine markedly. It is also available in ointment or aerosol preparations for a variety of topical appHcations. 

Mepivacaine hydrochloride [1722-62-9] similar in profile to Hdocaine, is used for infiltration, peripheral nerve blocks, and extradural anesthesia. It appears to be less toxic than Hdocaine in adults but more toxic in newborns. The duration of action is longer than that of Hdocaine because of its lower vasodilator activity. Mepivacaine has Htde topical activity. 

Fig. 2. Biosynthetic pathway for epinephrine, norepinephrine, and dopamine. The enzymes cataly2ing the reaction are (1) tyrosine hydroxylase (TH), tetrahydrobiopterin and O2 are also involved (2) dopa decarboxylase (DDC) with pyridoxal phosphate (3) dopamine-P-oxidase (DBH) with ascorbate, O2 in the adrenal medulla, brain, and peripheral nerves and (4) phenethanolamine A/-methyltransferase (PNMT) with. Cadenosylmethionine in the adrenal...

Peripheral nerve dysfunction (slowed nerve conduction)... 

Hyoscyamine. The natural alkaloid, 1-hyoscyamine and its d-isomeride resemble atropine (dl-hyoscyamine) qualitatively in action, but the 1-form acts more strongly on the peripheral nerves than the d- or dl-forms, though the isomerides appear to have an equal central action. 

Anchusa officinalis L. Cynoglossine B. HCl, crystalline. Paralyses peripheral nerve terminations. Consolidine gluco-alkaloid hydrolysed to glucose and consolicine (also present as such). Paralyses the central nervous system. The same alkaloids are also present in Echium vulgare L. and Cynoglossum offikinale L. (Greiner, Arch. Pharm., 1900, 238, 505). 

GABA is the predominant inhibitory neurotransmitter in the CNS. Baclofen acts centrally as an agonist at the GABAb receptor, which increases inhibition of nerves. 3-Aminopropylphosphinic acid (3-APPi) has been shown experimentally to act as an antitussive at peripheral nerves and preclinical evidence suggests that baclofen indeed has antitussive actions clinically [3]. 

BW443C is a novel opioid used for the treatment of cough, but which does not enter the brain and so exerts its effects only on peripheral nerves. It has not been tested as an antitussive in humans due to its rapid metabolism in the lungs but the concqrt of a peripheral opioid is still possible. 

Local anaesthetics are drugs that reversibly interrupt impulse propagation in peripheral nerves thus leading to autonomic nervous system blockade, analgesia, anaesthesia and motor blockade in a desired area of the organism. 

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

A peripheral nerve comprises different axons responsible for different modalities. It may contain efferent myelinated motor fibres, efferent unmyelinated autonomic fibres... 

Peripheral neuropathy is degeneration of peripheral nerves. Because motor and sensory axons tun in the same nerves, usually both motor and sensory functions are affected in this disease. Neuropathies may be either acute (e.g., Charcot-Marie-Tooth disease) or chronic (e.g., Guillain-Barre syndrome) and are categorized as demyelinating or axonal. 

Sensory nerves are peripheral nerves involved in the detection of exogenous and endogenous stimuli for transmission into the CNS. They can be subdivided into RARs and C-fibres according to their channel characteristics. 

NF1 neurofibromatosis type 1 benign and malignant peripheral nerve sheath tumors... 

Leprosy is a chronic, communicable disease spread by prolonged, intimate contact with an infected person. Peripheral nerves are affected, and skin involvement is present. Lesions may be confined to a few isolated areas or may be fairly widespread over the entire body. Treatment with the leprostatic drugs provides a good prospect for controlling the disease and preventing complications. 

Emetine emetine is still used at high doses for the treatment of patients with severe amebiasis. Muscle damage is uncommon but when it does occur can be a severe generalized necrotizing myopathy. The outcome is, at times, fatal, especially when an emetine-induced cardiomyopathy is also present. Despite the suggestion that there may be neuritic changes, there is no evidence that emetine damages peripheral nerve. The myopathy is usually painful but reversible. The mechanism of action of emetine is unknown. 

Chamberlain LJ, Yannas EV, Arrizabalaga A, Hsu HP, Norregaard TV, and Specter M. Early peripheral nerve healing in collagen and silicone tube imolants Myofibroblasts and the cellular response. Biomaterials, 1998, 19, 1393-1403. 

Aging of inhibited enzyme leads to degeneration of peripheral nerves... 

We proposed the term psychoneurogenic for the mechanism of these reactions, since the direct action on the nerve might elicit a reflex cascade via the CNS and then lead to the above-mentioned symptoms. Why these reactions only occur in certain individuals, maybe due to pharmacogenomics and specific hyperexcitability of peripheral nerves, remains open for speculation. There is a high degree of psychosomatic involvement in such reactions. 

B, Thiamin Coenzyme in pyruvate and a-ketoglutarate, dehydrogenases, and transketolase poorly defined function in nerve conduction Peripheral nerve damage (beriberi) or central nervous system lesions (Wernicke-Korsakoff syndrome)... 

Kleinschnitz C, Brinkhoff J, Zelenka M, Sommer C, Stoll G (2004) The extent of cytokine induction in peripheral nerve lesions depends on the mode of injury and NMDA receptor signaling. J Neuroimmunol 149(l-2) 77-83... 

The earliest reports of neurological complications of AIDS described distal symmetrical, painful sensory neuropathy occurring in HIV patients (Snider et al. 1983). Dysimmune inflammatory polyneuropathy was subsequently recognized as a complication of AIDS (Lipkin et al. 1985). Progressive polyneuropathy associated with cytomegalovirus (CMV) infection was documented as the first truly opportunistic infection of the peripheral nerve (Eidelberg et al. 1986). 

Diffuse infiltrative lymphocytosis syndrome AIDS Subacute Sjogren s-hke symmetric or asymmetric sensorimotor, painful, multiple mononeuritis or distal sensory neuropathy Angiocentric CDS hyperlymphocytosis in peripheral nerves vascular mural necrosis... 

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