Animal models in the neurotoxicology of 2,4-D

2,4-D is a selective pre- and postemergence herbicide used for several crops. It is hazardous for the environment and risk for humans; therefore, several studies attempt to evaluate its effects and consequences of its use. The nervous system is supposedly a target for this herbicide, and this comprehensive review gathers the information about animal models that have been used for the study of the neurotoxicity of 2,4-D. The studies used several methods to evaluate the neurotoxicity of this herbicide, most of which used rodents, mainly rats, two used fish, and one used chicken eggs. The main behavioral effect observed concerned alterations in locomotor patterns and reduced motor activity. Biochemical analysis showed decreased levels of serotonin (5-HT) and increased levels of its metabolites and increased or decreased levels of DA and its metabolites depending on the brain area analyzed. Hypomyelination is also a possible effect of 2,4-D when the exposure occurs during the proliferation and development of the oligodendrocytes. The worst neuropathologic effects were observed in fish. Since most studies focused on the neurotoxicity of 2,4-D in rodents, the effect it may have on other species and groups of animals, especially with different physiology, is unclear and it should be researched.

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Homoeopathic effect on the sleep pattern of rats

British Homeopathic Journal ◽

10.1016/s0007-0785(97)80045-2 ◽

1997 ◽

Vol 86 (04) ◽

pp. 201-206 ◽

Cited By ~ 10

Author(s):

José-Leonel Torres ◽

Guadalupe Ruiz

Keyword(s):

Central Nervous System ◽

Nervous System ◽

Veterinary Medicine ◽

Animal Models ◽

Pure Water ◽

Physiological Data ◽

Statistical Parameters ◽

Scientific Support ◽

Healthy Humans ◽

The Brain

AbstractThe effect of Nux vomica on the EEGs of rats during sleep was quantified in terms of suitable statistical parameters that showed systematic changes after the homoeopathic stimulus. Our results are consistent with a decrease in the coherence of the brain signal compared to results obtained by using either the solvent on its own or pure water, and can be interpreted in terms of irritation of the animals' central nervous system due to the applied stimulus. This coincides with the effect Nux vomica has on healthy humans and suggests a means of characterizing the homoeopathic effect in physicochemical terms, based on parameters similar to those found appropriate in this study, calculated for physiological data from animal models for specific conditions. It also lends scientific support to ongoing attempts to extend Hahnemann's principles of similitude and potentiation beyond their original context, into the realm of veterinary medicine.

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Evaluation of the Anticonvulsant Activity of Terpinen-4-ol

Zeitschrift für Naturforschung C ◽

10.1515/znc-2009-1-201 ◽

2009 ◽

Vol 64 (1-2) ◽

pp. 1-5 ◽

Cited By ~ 12

Author(s):

Damião P. de Sousa ◽

Franklin F. F. Nóbrega ◽

Liana C. S. L. de Morais ◽

Reinaldo N. de Almeida

Keyword(s):

Central Nervous System ◽

Nervous System ◽

Animal Models ◽

Motor Activity ◽

Anticonvulsant Activity ◽

Maximal Electroshock ◽

Aromatic Plants ◽

Depressant Effect ◽

Maximal Electroshock Seizure ◽

The Central Nervous System

Terpinen-4-ol is a monoterpenoid alcohol and component of the essential oils of several aromatic plants. Similarly to terpinen-4-ol, other monoterpenoid alcohols have shown anticonvulsant activity in convulsion animal models. The present study aimed to investigate the anticonvulsant activity of terpinen-4-ol. Treatment of mice with terpinen-4-ol ( 200 mg/kg) caused a signifi cant decrease in the spontaneous motor activity at 30, 60 and 120 min after administration. Terpinen-4-ol (100 and 200 mg/kg) produced a significant dosedependent increase in the duration of sleeping in mice. Pretreatment of mice with terpinen-4- ol at doses of 100, 200 and 300 mg/kg significantly increased the latency of pentylenetetrazole -induced convulsions. Terpinen-4-ol (200 and 300 mg/kg) also inhibited the induced seizures of picrotoxin. In another model, maximal electroshock seizure, terpinen-4-ol decreased the tonic hind convulsions percentage at the dose of 300 mg/kg. From the overall results we can conclude that terpinen-4-ol showed a depressant effect on the central nervous system and significant anticonvulsant activity.

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Environmental Enrichment and Neuronal Plasticity

The Oxford Handbook of Developmental Neural Plasticity ◽

10.1093/oxfordhb/9780190635374.013.13 ◽

2018 ◽

Cited By ~ 3

Author(s):

Gregory D. Clemenson ◽

Fred H. Gage ◽

Craig E.L. Stark

Keyword(s):

Animal Models ◽

Neuronal Plasticity ◽

Environmental Enrichment ◽

Structural Changes ◽

Positive Impact ◽

Laboratory Animals ◽

Complete Understanding ◽

Comprehensive Review ◽

Spatial Exploration ◽

The Brain

This chapter reviews the literature on environmental enrichment and specifically discusses its influence on the hippocampus of the brain. In animal models, the term “environmental enrichment” is used to describe a well-defined manipulation in which animals are exposed to a larger and more stimulating environment. This experience has been shown to have a powerful and positive impact on hippocampal cognition and neuroplasticity in animals. In humans, however, the translation of environmental enrichment is less clear. Despite the fact that humans live considerably more enriching lives compared to laboratory animals, studies have shown that training and expertise (such as exercise and spatial exploration) can lead to both functional and structural changes in the human brain. This chapter is a comprehensive review of environmental enrichment, drawing parallels between animal models and humans to present a more complete understanding of environmental enrichment.

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Mining for survival genes

Biochemical Society Transactions ◽

10.1042/bst0341307 ◽

2006 ◽

Vol 34 (6) ◽

pp. 1307-1309 ◽

Cited By ~ 3

Author(s):

V.L. Dawson ◽

T.M. Dawson

Keyword(s):

Central Nervous System ◽

Nervous System ◽

Animal Models ◽

Human Brain ◽

Protective Mechanism ◽

Protective Mechanisms ◽

Central Nervous System Disorders ◽

Organ Systems ◽

Gene And Protein Expression ◽

The Brain

Many stressful, but not lethal, stimuli activate endogenous protective mechanisms that significantly decrease the degree of injury to subsequent injurious stimuli. This protective mechanism is termed preconditioning and tolerance. It occurs across organ systems including the brain and nervous system. Preconditioning has been investigated in cell and animal models and recently been shown to potentially occur in human brain. Learning more about these powerful endogenous neuroprotective mechanisms could help identify new approaches to treat patients with stroke and other central nervous system disorders or injury. Cell and animal models are helping us to better understand the network response of gene and protein expression that activates the neuroprotective response.

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Subchronic Neurotoxicity of Vaporized Diisopropyl Ether in Rats

International Journal of Toxicology ◽

10.1080/109158197226919 ◽

1997 ◽

Vol 16 (6) ◽

pp. 599-610 ◽

Cited By ~ 3

Author(s):

S. C. Rodriguez ◽

W. E. Dalbey

Keyword(s):

Nervous System ◽

Motor Activity ◽

Microscopic Examination ◽

Diisopropyl Ether ◽

Sprague Dawley ◽

Clinical Observations ◽

Sprague Dawley Rats ◽

Body Weights ◽

Group Sex ◽

The Brain

The neurotoxicity potential of diisopropyl ether (DIPE) during subchronic exposures was evaluated in rats using a functional observational battery (FOB), automated motor activity, and neuropathology. Sprague-Dawley rats were exposed 5 dl wk for 13 weeks by inhalation to either 0, 450, 3250, or 7060 ppm DIPE. Body weights were recorded weekly and clinical observations were recorded prior to each exposure. The FOB and a measurement of motor activity were performed before the first exposure. The FOB was repeated following 2, 4, 8, and 13 weeks of exposure, and motor activity was determined following 4, 8, and 13 weeks of exposure. After completion of the final evaluations, the animals were intravascularly perfused with phosphate-buffered 5% glutaraldehyde. Microscopic examination of the brain, spinal cord, gasserian and dorsal root ganglia, and sciatic nerve was performed on six animals/ group/ sex exposed to 0 or 7060 ppm DIPE. Motor activity in a figure-eight maze and unperturbed activity in the FOB were decreased at week 4 in females exposed to 7060 ppm; activity in the FOB was also decreased in females exposed to 450 ppm at week 4. Other changes in the FOB appeared to be minor, and none were observed during microscopic examination of tissues from the nervous system. In conclusion, inhalation exposures to DIPE at concentrations as high as 7060 ppm for 13 weeks resulted in few observable effects on the nervous system.

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Glucuronyl 3-sulfate occurs exclusively on distal unmyelinated terminals of selected sensory neurons in the peripheral nervous system

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100141160 ◽

1995 ◽

Vol 53 ◽

pp. 958-959

Author(s):

S.S. Spicer ◽

B.A. Schulte

Keyword(s):

Central Nervous System ◽

Nervous System ◽

Cerebral Cortex ◽

Peripheral Nervous System ◽

Sensory Neurons ◽

Sensory Nerves ◽

Tissue Antigens ◽

The Central Nervous System ◽

The Brain ◽

Leu 7

Generation of monoclonal antibodies (MAbs) against tissue antigens has yielded several (VC1.1, HNK- 1, L2, 4F4 and anti-leu 7) which recognize the unique sugar epitope, glucuronyl 3-sulfate (Glc A3- SO4). In the central nervous system, these MAbs have demonstrated Glc A3-SO4 at the surface of neurons in the cerebral cortex, the cerebellum, the retina and other widespread regions of the brain.Here we describe the distribution of Glc A3-SO4 in the peripheral nervous system as determined by immunostaining with a MAb (VC 1.1) developed against antigen in the cat visual cortex. Outside the central nervous system, immunoreactivity was observed only in peripheral terminals of selected sensory nerves conducting transduction signals for touch, hearing, balance and taste. On the glassy membrane of the sinus hair in murine nasal skin, just deep to the ringwurt, VC 1.1 delineated an intensely stained, plaque-like area (Fig. 1). This previously unrecognized structure of the nasal vibrissae presumably serves as a tactile end organ and to our knowledge is not demonstrable by means other than its selective immunopositivity with VC1.1 and its appearance as a densely fibrillar area in H&E stained sections.

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Ultrastructural morphology of neurosecretory neurons in the barnacle Balanus amphitrite

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100159710 ◽

1990 ◽

Vol 48 (3) ◽

pp. 434-435

Author(s):

Grazia Tagliafierro ◽

Cristiana Crosa ◽

Marco Canepa ◽

Tiziano Zanin

Keyword(s):

Nervous System ◽

Ultrastructural Level ◽

Uranyl Acetate ◽

Balanus Amphitrite ◽

Neurosecretory Neurons ◽

The Central Nervous System ◽

Ultrathin Sections ◽

Dense Core Granules ◽

The Brain ◽

Ocellar Nerve

Barnacles are very specialized Crustacea, with strongly reduced head and abdomen. Their nervous system is rather simple: the brain or supra-oesophageal ganglion (SG) is a small bilobed structure and the toracic ganglia are fused into a single ventral mass, the suboesophageal ganglion (VG). Neurosecretion was shown in barnacle nervous system by histochemical methods and numerous putative hormonal substances were extracted and tested. Recently six different types of dense-core granules were visualized in the median ocellar nerve of Balanus hameri and serotonin and FMRF-amide like substances were immunocytochemically detected in the nervous system of Balanus amphitrite. The aim of the present work is to localize and characterize at ultrastructural level, neurosecretory neuron cell bodies in the VG of Balanus amphitrite.Specimens of Balanus amphitrite were collected in the port of Genova. The central nervous system were Karnovsky fixed, osmium postfixed, ethanol dehydrated and Durcupan ACM embedded. Ultrathin sections were stained with uranyl acetate and lead citrate. Ultrastructural observations were made on a Philips M 202 and Zeiss 109 T electron microscopy.

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Complex Trauma and Prenatal Alcohol Exposure: Clinical Implications

Perspectives on School-Based Issues ◽

10.1044/sbi13.2.32 ◽

2012 ◽

Vol 13 (2) ◽

pp. 32-42 ◽

Cited By ~ 8

Author(s):

Yvette D. Hyter

Keyword(s):

Central Nervous System ◽

Nervous System ◽

Child Development ◽

Academic Outcomes ◽

Complex Trauma ◽

Prenatal Alcohol Exposure ◽

Alcohol Exposure ◽

Clinical Implications ◽

Prenatal Alcohol ◽

The Brain

Abstract Complex trauma resulting from chronic maltreatment and prenatal alcohol exposure can significantly affect child development and academic outcomes. Children with histories of maltreatment and those with prenatal alcohol exposure exhibit remarkably similar central nervous system impairments. In this article, I will review the effects of each on the brain and discuss clinical implications for these populations of children.

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Central Nerve System Impairment, AMA Guides, Sixth Edition: An Overview

Guides Newsletter ◽

10.1001/amaguidesnewsletters.2018.janfeb03 ◽

2018 ◽

Vol 23 (1) ◽

pp. 10-13

Author(s):

James B. Talmage ◽

Jay Blaisdell

Keyword(s):

Spinal Cord ◽

Central Nervous System ◽

Nervous System ◽

Neurological Impairment ◽

Sixth Edition ◽

Central Nerve System ◽

The Central Nervous System ◽

The One ◽

Nerve System ◽

The Brain

Abstract Injuries that affect the central nervous system (CNS) can be catastrophic because they involve the brain or spinal cord, and determining the underlying clinical cause of impairment is essential in using the AMA Guides to the Evaluation of Permanent Impairment (AMA Guides), in part because the AMA Guides addresses neurological impairment in several chapters. Unlike the musculoskeletal chapters, Chapter 13, The Central and Peripheral Nervous System, does not use grades, grade modifiers, and a net adjustment formula; rather the chapter uses an approach that is similar to that in prior editions of the AMA Guides. The following steps can be used to perform a CNS rating: 1) evaluate all four major categories of cerebral impairment, and choose the one that is most severe; 2) rate the single most severe cerebral impairment of the four major categories; 3) rate all other impairments that are due to neurogenic problems; and 4) combine the rating of the single most severe category of cerebral impairment with the ratings of all other impairments. Because some neurological dysfunctions are rated elsewhere in the AMA Guides, Sixth Edition, the evaluator may consult Table 13-1 to verify the appropriate chapter to use.

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