The thyroid and the development of the nervous system in Eleutherodactylus martinicensis: an experimental study

Development ◽  
1966 ◽  
Vol 16 (3) ◽  
pp. 401-430
Author(s):  
Arthur Hughes
Keyword(s):  
Experimental Study ◽  
Nervous System ◽  
Thyroid Hormones ◽  
Peripheral Nervous System ◽  
Peripheral Nerves ◽  
Hind Limb ◽  
Endocrine System ◽  
Normal Embryo ◽  
Stages Of Development ◽  
Quantitative Studies

In a recent paper (Hughes, 1965a) the ontogeny of the peripheral nervous system in Eleutherodactylus martinicensis was studied by counting the numbers of constituent fibres in the nerves of the hind limb at several stages of development. Eleutherodactylus is one of the smallest of living tetrapods and such quantitative studies are aided by the comparatively small numbers of fibres within its peripheral nerves. The next step in the analysis of the various changes which occur simultaneously in the normal embryo is to attempt to disengage them by some treatment which affects the general course or development. Interference with the endocrine system of the embryo is one obvious line of investigation, more particularly as a number of events in the development of the nervous system in other vertebrates have been shown to be influenced by thyroid hormones. The action of the thyroid in Eleutherodactylus has already been investigated by Lynn & Peadon (1955).

Some effects of de-afferentation on the developing amphibian nervous system

Development ◽  
1965 ◽  
Vol 14 (1) ◽  
pp. 75-87
Author(s):  
Arthur Hughes
Keyword(s):  
Nervous System ◽  
Quantitative Study ◽  
Peripheral Nerves ◽  
Hind Limb ◽  
Sensory Input ◽  
Bufo Marinus ◽  
Degenerative Changes ◽  
Normal Embryo

An adult anuran can still walk or swim if the nerves supplying one or even two limbs are de-afferentated (Gray, 1950). However, in a developing amphibian, a limb at motile stages becomes paralysed when deprived of its sensory input. A sequence of degenerative changes then follow in the cord and in peripheral nerves. Tadpoles of Bufo marinus and late embryos of Eleutherodactylus martinicensis have been submitted to this experiment; in these tropical forms the subsequent events follow rapidly. Most attention has been paid to Eleutherodactylus, on which a quantitative study of the numbers of fibres in nerves to the hind limb during development has recently been published (Hughes, 1965a). This work, together with a study of the behaviour of the normal embryo (Hughes, 1965b) has been used as a basis for the present experimental observations. The source of the embryos of E. martinicensis and the methods of culturing and observing them remain the same as in previous studies (Hughes, 1962,1964a & b, 1965a & b).

scholarly journals Induction of Type 3 Iodothyronine Deiodinase by Nerve Injury in the Rat Peripheral Nervous System

Endocrinology ◽  
2001 ◽  
Vol 142 (12) ◽  
pp. 5190-5197 ◽  
Author(s):  
Wen Wu Li ◽  
Claude Le Goascogne ◽  
Martine Ramaugé ◽  
Michael Schumacher ◽  
Michel Pierre ◽  
...  
Keyword(s):  
Nervous System ◽  
Sciatic Nerve ◽  
Thyroid Hormones ◽  
Peripheral Nervous System ◽  
Distal Segment ◽  
Nerve Lesion ◽  
Adult Rats ◽  
Iodothyronine Deiodinase ◽  
Cultured Fibroblasts ◽  
Type 3

Abstract Thyroid hormones are essential for the development and repair of the peripheral nervous system. The type 2 deiodinase, which is responsible for the activation of T4 into T3, is induced in injured sciatic nerve. To obtain information on the type 3 deiodinase (D3) responsible for the degradation of thyroid hormones, we looked for its expression (mRNA and activity) in the sciatic nerve after injury. D3 was undetectable in the intact sciatic nerve of adult rats, but was rapidly and highly increased in the distal and proximal segments after nerve lesion. After cryolesion, D3 up-regulation disappeared after 3 d in the proximal segment, whereas it was sustained for 10 d in the distal segment, then declined to reach basal levels after 28 d, when functional recovery was completed. After a transsection preventing the nerve regeneration, up-regulation of D3 persisted up to 28 d at high levels in the distal segment. D3 was expressed in peripheral connective sheaths and in the internal endoneural compartment. D3 mRNA was inducible by 12-O-tetradecanoylphorbol-13-acetate in cultured fibroblasts or Schwann cells. In conclusion, induction of D3 in the peripheral nervous system after injury may play an important role during the regeneration process by adjusting intracellular T3 levels.

scholarly journals Glioendocrine System: Effects of Thyroid Hormones in Glia and their Functions in the Central Nervous System

2020 ◽  
Vol 3 (1) ◽  
pp. 1-11
Author(s):  
Mami Noda
Keyword(s):  
Central Nervous System ◽  
Nervous System ◽  
Cognitive Impairment ◽  
Thyroid Hormones ◽  
Glial Cells ◽  
Endocrine System ◽  
Cell Types ◽  
Development And Differentiation ◽  
The Central Nervous System ◽  
And Function

AbstractGlial cells play a significant role in the link between the endocrine and nervous systems. Among hormones, thyroid hormones (THs) are critical for the regulation of development and differentiation of neurons and glial cells, and hence for development and function of the central nervous system (CNS). THs are transported into the CNS, metabolized in astrocytes and affect various cell types in the CNS including astrocyte itself. Since 3,3’,5-triiodo-L-thyronine (T3) is apparently released from astrocytes in the CNS, it is a typical example of glia-endocrine system.The prevalence of thyroid disorders increases with age. Both hypothyroidism and hyperthyroidism are reported to increase the risk of cognitive impairment or Alzheimer’s disease (AD). Therefore, understanding the neuroglial effects of THs may help to solve the problem why hypothyroidism or hyperthyroidism may cause mental disorders or become a risk factor for cognitive impairment. In this review, THs are focused among wide variety of hormones related to brain function, and recent advancement in glioendocrine system is described.

scholarly journals ДИНАМИКА ИЗМЕНЕНИЙ СТРУКТУР ПАРАНЕВРИЯ В ПОСТНАТАЛЬНОМ ОНТОГЕНЕЗЕ

Innova ◽  
2020 ◽  
pp. 26-28
Author(s):  
Бородина К.А. ◽  
Затолокина М.А. ◽  
Харченко В.В. ◽  
Затолокина М.А. ◽  
Мишина Е.С. ◽  
...  
Keyword(s):  
Nervous System ◽  
Peripheral Nerve ◽  
Peripheral Nervous System ◽  
Peripheral Nerves ◽  
Full Range ◽  
Structural Features ◽  
Morphological Features ◽  
Depth Data ◽  
Age Related

Currently, there is a lot of literature and research that reflects data on the structure of the peripheral nervous system. However, it should be noted that the results available in the sources do not contain a full range of data on the structural features of paraneural structures and have some contradictions. In addition, data on the morphological features of the structure of the paranephrium of peripheral nerves in ontogenesis are practically absent. This was the beginning of our research, in order to obtain new, more in-depth data on the age-related variability of the peripheral nerve paraneurium.

Peripheral Nerves: Not Only Cross-sectional Area in the Era of Radiomics

2020 ◽  
Vol 24 (02) ◽  
pp. 175-180
Author(s):  
Alberto Stefano Tagliafico ◽  
Raquel Prada González ◽  
Federica Rossi ◽  
Bianca Bignotti ◽  
Carlo Martinoli
Keyword(s):  
Nervous System ◽  
Peripheral Nerve ◽  
Peripheral Nervous System ◽  
Internal Control ◽  
Peripheral Nerves ◽  
Imaging Techniques ◽  
Cross Sectional Area ◽  
Sectional Area ◽  
Musculoskeletal Radiology ◽  
Cross Sectional

AbstractThe peripheral nervous system is increasingly being investigated using medical imaging as a complement or in association with electrodiagnostics tests. The application of imaging techniques, such as ultrasound (US) and magnetic resonance imaging (MRI), allows detailed visualization of the peripheral nervous system. According to the European Society of Musculoskeletal Radiology, the use of US for nerve evaluation is strongly encouraged. In addition, the role of US is further enhanced by the wide application of US-guided techniques to diagnose or to treat peripheral nerve disorders.Standard evaluation of peripheral nerves on US usually relies on cross-sectional area evaluation with different cutoff values in the osteofibrous tunnels and outside them. In several anatomical areas, side-to-side comparison is highly recommended because it helps distinguish subtle variations by using the unaffected limb as an internal control.US is widely used to perform US-guided interventional procedures on peripheral nerves. The recent development of radiomics and machine and deep learning applied to peripheral nerves may reveal new insights beyond the capabilities of the human eye. Radiomics may have a role in expanding the diagnostic capabilities of US and MRI in the study of peripheral nerve pathology, especially when the cross-sectional area is not markedly increased.

scholarly journals Liver X Receptors and Their Implications in the Physiology and Pathology of the Peripheral Nervous System

2019 ◽  
Vol 20 (17) ◽  
pp. 4192
Author(s):  
Venkat Krishnan Sundaram ◽  
Charbel Massaad ◽  
Julien Grenier
Keyword(s):  
Nervous System ◽  
Peripheral Nervous System ◽  
Sensory Neurons ◽  
Peripheral Nerves ◽  
Therapeutic Potential ◽  
Positive Impact ◽  
Redox Homeostasis ◽  
Liver X Receptors ◽  
X Receptors

Recent research in the last decade has sought to explore the role and therapeutic potential of Liver X Receptors (LXRs) in the physiology and pathologies of the Peripheral Nervous System. LXRs have been shown to be important in maintaining the redox homeostasis in peripheral nerves for proper myelination, and they regulate ER stress in sensory neurons. Furthermore, LXR stimulation has a positive impact on abrogating the effects of diabetic peripheral neuropathy and obesity-induced allodynia in the Peripheral Nervous System (PNS). This review details these findings and addresses certain important questions that are yet to be answered. The potential roles of LXRs in different cells of the PNS are speculated based on existing knowledge. The review also aims to provide important perspectives for further research in elucidating the role of LXRs and assessing the potential of LXR based therapies to combat pathologies of the Peripheral Nervous System.

scholarly journals The effect of peripheral nervous system in growing bone biomechanics. An experimental study

2019 ◽  
Vol 16 (3) ◽  
pp. 289-292 ◽  
Author(s):  
Ioannis Gkiatas ◽  
Ioannis Kostas-Agnantis ◽  
Symeon Agathopoulos ◽  
Dimitrios Papadopoulos ◽  
Marios Vekris ◽  
...  
Keyword(s):  
Experimental Study ◽  
Nervous System ◽  
Peripheral Nervous System ◽  
Bone Biomechanics

Neuropathies in the older patient

2006 ◽  
Vol 16 (2) ◽  
pp. 113-124 ◽  
Author(s):  
Yusuf A Rajabally
Keyword(s):  
Nervous System ◽  
Peripheral Neuropathy ◽  
Peripheral Nervous System ◽  
Peripheral Nerves ◽  
Elderly Population ◽  
Natural Aging ◽  
The Elderly ◽  
Impaired Glucose Metabolism ◽  
Older Patient ◽  
Target Organs

Peripheral neuropathy encompasses disorders of the peripheral nervous system, affecting the axon and/or the myelin sheath. The prevalence of peripheral neuropathy increases with age. Thought to be of about 3000 per 100 000 in adults generally, this figure could be as high as 8000 above the age of 60 years. However more than half of these cases would be due to impaired glucose metabolism in its various forms. In the remainder, an aetiology may be found in about 70% of cases. The elderly population is at higher risk of peripheral neuropathy, as there is a correlation between age and impairment of the peripheral nervous system. The natural aging process affects adversely the function of peripheral nerves and of their target organs, resulting in the development of motor, sensory and autonomic symptoms in the absence of additional damage of other causes. In addition, the increased prevalence of chronic systemic disorders causing neuropathy, as well as the use of neurotoxic drugs in older patients, contribute to the onset of neuropathy.

scholarly journals Diagnostic significance of electroneuromyographic (enmg) indices in diphtheria polyneuropathy

1997 ◽  
Vol XXIX (1-2) ◽  
pp. 67-69
Author(s):  
V. N. Komantsev ◽  
М. N. Sorokina ◽  
N. V. Skripchenko
Keyword(s):  
Nervous System ◽  
Peripheral Nervous System ◽  
Peripheral Nerves ◽  
Lower Extremities ◽  
The State ◽  
Diagnostic Significance ◽  
Initial Symptoms ◽  
F Wave ◽  
Wave Latency

There studied changes of electroneuiomyographical indices for evaluation of incidence and dynamics of lesion of peripheral nervous system during diphtheria. For this purpose 37 patients with diphtheria polyneuropathy at the age of 214 years at different terms of disease were examined. It was shown that during diphtheria most often the nerves of lower extremities are damaged: fibular and tibial. Information of ENMG indices of the latter is more significant. For revealing the initial symptoms of the nervous system lesion it is useful to investigate the state of myelinization of proximal parts of peripheral nerves according to F-wave latency.

scholarly journals Progressive Degeneration and Inhibition of Peripheral Nerve Regeneration in the SOD1-G93A Mouse Model of Amyotrophic Lateral Sclerosis

2018 ◽  
Vol 46 (6) ◽  
pp. 2358-2372 ◽  
Author(s):  
Binbin Deng ◽  
Wenjing Lv ◽  
Weisong Duan ◽  
Yakun Liu ◽  
Zhongyao Li ◽  
...  
Keyword(s):  
Amyotrophic Lateral Sclerosis ◽  
Nervous System ◽  
Schwann Cell ◽  
Mouse Model ◽  
Peripheral Nerve ◽  
Peripheral Nervous System ◽  
Peripheral Nerves ◽  
Mutant Mice ◽  
Sod1 Mutant ◽  
Lateral Sclerosis

Background: Myelination, degeneration and regeneration are implicated in crucial responses to injury in the peripheral nervous system. Considering the progression of amyotrophic lateral sclerosis (ALS), we used the superoxide dismutase 1 (SOD1)-G93A transgenic mouse model of ALS to investigate the effects of mutant SOD1 on the peripheral nerves. Methods: Changes in peripheral nerve morphology were analyzed in SOD1 mutant mice at various stages of the disease by toluidine blue staining and electron microscopy (EM). Schwann cell proliferation and recruitment of inflammatory factors were detected by immunofluorescence staining and quantitative reverse transcription PCR and were compared between SOD1 mutant mice and control mice. Furthermore, western blotting (WB) and TUNEL staining were used to investigate axonal damage and Schwann cell survival in the sciatic nerves of mice in both groups. Results: An analysis of the peripheral nervous system in SOD1-G93A mice revealed the following novel features: (i) Schwann cells and axons in mutant mice underwent changes that were similar to those seen in the control mice during the early development of peripheral nerves. (ii) The peripheral nerves of SOD1-G93A mice developed progressive neuropathy, which presented as defects in axons and myelin, leading to difficulty in walking and reduced locomotor capacity at a late stage of the disease. (iii) Macrophages were recruited and accumulated, and nerve injury and a deficit in the blood-nerve barrier were observed. (iv) Proliferation and the inflammatory micro-environment were inhibited, which impaired the regeneration and remyelination of axons after crush injury in the SOD1-G93A mice. Conclusions: The mutant human SOD1 protein induced axonal and myelin degeneration during the progression of ALS and participated in axon remyelination and regeneration in response to injury.

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