Effects on the Peripheral Nervous System

The effects of neurotoxic chemicals upon nerve action potential have been measured both in vertebrates and insects. Of particular interest has been the comparison 

In one example (Lawrence and Casida 1984, Abalis et al. 1985) rat brain microsacs were used to test the action of cyclodiene insecticides such as dieldrin and endrin on the GABA receptors contained therein. The influx of radiolabeled CL into the microsacs via the pore channel of the receptor was inhibited by these chemicals. A similar assay was developed using microsacs from cockroach nerve. Assays with this preparation showed again the inhibitory effect of a cyclodiene (this time heptachlor epoxide) on CL influx. Also, that microsacs from cyclodiene resistant cockroaches were insensitive to the inhibitory effect of picrotoxinin, which binds to the same site on the GABA receptor (Kadous et al. 1983). 

Organic Pollutants An Ecotoxicological Perspective, Second Edition 

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Johnson BL, Boyd J, Burg JR, et al. 1983. Effects on the peripheral nervous system of workers exposure to carbon disulfide. Neurotoxicology 4(l) 53-66. 

The solanaceae alkaloids and other other sources of antimuscarinics affect the CNS. They can produce hallucinations in addition to their effects on the peripheral nervous system. Witchcraft of the Middle Ages produced mixtures of plants - deadly nightshade, monkshood, and hemlock among them - as "flying ointments". The combined toxins disturbed the rhythm of the heart and led to delirium which could create a sensation of rising and falling, that is, flying. 

Kava s effects on the peripheral nervous system are limited to a local anesthetic effect, resulting in numbness in the mouth if kava is chewed (1). Lipid-soluble kava extract, or resin, is also capable of causing anesthesia of the oral mucosa, whereas the water-soluble fraction is not (9). 

Pesticide chemicals are related to specific toxic effects. With the soil fumigants, reproductive effects and carcinogenicity are the main concern. With the carbamates, such as aldicarb, we are concerned with an acute toxic effect on the peripheral nervous system. With pentachlorophenol high acute toxicity and the potential for carcinogenicity are the main concerns. 

C HjjNOj, Mr 289.37, needles, mp, 106-108 °C, [ain -22° (50% C2H5OH/H2O), A tropane alkaloid form numerous Solanaceae genera such as, e.g. Atropa (deadly nightshade). Datura (thorn apple), Du-boisia, Hyoscyamus (henbane), and Scopolia (banewort). H. racemizes slowly in alcoholic solution, rapidly in alkaline and acidic solutions and in molten state to atropine. It has the same effects on the central nervous system as atropine and a twice as strong toxic effect on the peripheral nervous system [LD50 (mouse i. V.) 95 mg/kg]. Symptoms of poisoning include dry mouth and throat. For isolation from cell cultures, see Lit. For biosynthesis, see tropane alkaloids. 

Methyl methacrylate and 2-HEMA can cause paresthesia of the fingertips for months after discontinuation of contact with the monomer (Bohling et al. 1977 Matthias et al. 1979 Kanerva and Verkkala 1986). An effect on the peripheral nervous system has also been described for acrylamide (Edvards 1975). 

Cavaletti, G., E. CavaUetti, P. Montaguti, N. Oggioni, O. De Negri, and G. Tredici. 1997. Effect on the peripheral nervous system of the short-term intravenous administration of paclitaxel in the rat. Neurotoxicology 18 137-145. 

The potentials at neuromuscular junctions, the ganglionic potentials and the so called generator potentials of the receptor cells are taken into consideration in the study of drug effects on the peripheral nervous system. 

The hypotensive action of clonidine could not be explained satisfactorily by effects on the peripheral circulation. Numerous studies therefore considered the possibility of an effect on the central nervous system. Investigations performed on spinalized animals could... 

Fig. 1. Peripheral and central mechanism of neuropathic pain caused by vincristine. The upper diagram shows the effect of vincristine on the peripheral nervous system (comprising Schwann cells and the dorsal root ganglion (DRG)) and the involvement of interleukin (IL)-6 derived from infiltrating macrophages in neuropathic pain caused by vincristine. The lower diagram shows the effect of vincristine on the central nervous system, and the involvement of tumor necrosis factor-a (TNF-a) derived from activated microglia and astrocytes in neuropathic pain caused by vincristine.

Inhalation anesthetics are nonselective in their action. That is, in addition to their clinically important effect on the central nervous system (CNS), they also alter the function of various peripheral cell types. The fact that chemically unrelated molecules produce a state of general anesthesia argues against a specific anesthetic receptor. Further, whereas anesthetics alter the function of receptors for neurotransmitters (for example, y-aminobutyric acid, glutamate),... 

Faravelli, D., Di Bernardo, M., Ricca, V., Benvenuti, P., Bartelli, M., Ronchi, O. (1999). Effects of chronic lithium treatment on the peripheral nervous system. Journal of Clinical Psychiatry, 60, 306-310. 

SAFETY PROFILE Poison by ingestion, inhalation, skin contact, intraperitoneal, intravenous, subcutaneous, and ocular routes. Human systemic effects by ingestion a cholinesterase inhibitor. Has been found to inhibit peripheral cholinesterase without pronounced effects on the central nervous system. An insecticide. When heated to decomposition it emits toxic fumes of NO and POx. See also PARATHION and ANHYDRIDES. 

The primary action is to bind irreversibly to the presyn-aptic nerve terminals of peripheral cholinergic nerve fibers. Because the drug does not penetrate the blood-brain barrier, it has no effect on the central nervous system. The binding of botulinum to the nerve terminals blocks the release of acetylcholine at the neuromuscular junction, resulting in a temporary paralysis of the muscle. 

Faravelli C, Di Bernardo M, Ricca V, Benvenuti P, Bartelli M, Ronchi O. Effects of chronic hthium treatment on the peripheral nervous system. J Clin Psychiatry 1999 60(5) 306-10. 

Cavaletti G, Tredici G, Petruccioh MG, Donde E, Tredici P, Marmiroh P, Minoia C, Ronchi A, Bayssas M, Etienne GG. Effects of different schedules of oxaliplatin treatment on the peripheral nervous system of the rat. Eur J Cancer 2001 37(18) 2457-63. 

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