Initiating morphological changes associated with long-term facilitation inAplysia is independent of transcription or translation in the cell body

Peter W. Grabham; Fang Wu; Samuel Schacher; Daniel J. Goldberg

doi:10.1002/neu.20133

Induction of long-term facilitation in Aplysia sensory neurons by local application of serotonin to remote synapses

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.90.23.11411 ◽

1993 ◽

Vol 90 (23) ◽

pp. 11411-11415 ◽

Cited By ~ 35

Author(s):

G A Clark ◽

E R Kandel

Keyword(s):

Gene Expression ◽

Sensory Neurons ◽

Cell Body ◽

Sensory Cells ◽

Target Cells ◽

Synaptic Terminals ◽

Dissociated Cell Culture ◽

Synaptic Changes ◽

Long Term Facilitation

Long-term synaptic facilitation at the connections of Aplysia sensory neurons onto their target cells involves alterations in gene expression. How then are the relevant cellular signals for the induction and expression of long-term synaptic changes conveyed between the nucleus and remote synaptic terminals? We have explored this question using a set of remote, peripheral terminals of siphon sensory cells, which are approximately 3 cm from the sensory cell body in the abdominal ganglion. We found that these remote synapses, like the proximal synapses previously studied in dissociated cell culture, can exhibit long-term facilitation 24 hr after cell-wide serotonin application. Furthermore, serotonin applications restricted to the remote synaptic terminals nevertheless produced long-term facilitation, indicating that signals generated in synaptic regions can trigger the long-term process, perhaps via retrograde signals to the nucleus to modify gene expression, followed by anterograde signals back to the terminal. Serotonin applications restricted to the cell body and proximal synapses of the sensory neuron also produced long-term facilitation at remote synapses, although to a lesser extent, suggesting that long-term facilitation is expressed cell-wide, but that superimposed on this cell-wide facilitation there appears to be a component that is synapse-specific.

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Protein synthesis at synapse versus cell body: Enhanced but transient expression of long-term facilitation at isolated synapses

Journal of Neurobiology ◽

10.1002/neu.10242 ◽

2003 ◽

Vol 56 (3) ◽

pp. 275-286 ◽

Cited By ~ 34

Author(s):

Ke Liu ◽

Jiang-Yuan Hu ◽

Denong Wang ◽

Samuel Schacher

Keyword(s):

Protein Synthesis ◽

Transient Expression ◽

Cell Body ◽

Long Term Facilitation

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Comparative assessment of morphological mechanisms of maintaining structural liver homeostasis in the dynamics of exposure to coal-rock dust and sodium fluoride on the body

Russian Journal of Occupational Health and Industrial Ecology ◽

10.31089/1026-9428-2020-60-3-189-194 ◽

2020 ◽

pp. 189-194

Author(s):

M. S. Bugaeva ◽

O. I. Bondarev ◽

N. N. Mikhailova ◽

L. G. Gorokhova

Keyword(s):

Sodium Fluoride ◽

Morphological Changes ◽

The Body ◽

System Level ◽

Production Factor ◽

Coal Rock ◽

The Impact ◽

Structural Homeostasis ◽

Rock Dust

Introduction. The impact on the body of such factors of the production environment as coal-rock dust and fluorine compounds leads to certain shift s in strict indicators of homeostasis at the system level. Maintaining the relative constancy of the internal environment of the body is provided by the functional consistency of all organs and systems, the leading of which is the liver. Organ repair plays a crucial role in restoring the structure of genetic material and maintaining normal cell viability. When this mechanism is damaged, the compensatory capabilities of the organ are disrupted, homeostasis is disrupted at the cellular and organizational levels, and the development of the main pathological processes is noted.The aim of the study is to compare the morphological mechanisms of maintaining structural homeostasis of the liver in the dynamics of the impact on the body of coal-rock dust and sodium fluoride.Materials and methods. Experimental studies were conducted on adult white male laboratory rats. Features of morphological mechanisms for maintaining structural homeostasis of the liver in the dynamics of exposure to coal-rock dust and sodium fluoride were studied on experimental models of pneumoconiosis and fluoride intoxication. For histological examination in experimental animals, liver sampling was performed after 1, 3, 6, 9, 12 weeks of the experiment.Results. The specificity of morphological changes in the liver depending on the harmful production factor was revealed. It is shown that chronic exposure to coal-rock dust and sodium fluoride is characterized by the development of similar morphological changes in the liver and its vessels from the predominance of the initial compensatory-adaptive to pronounced violations of the stromal and parenchymal components. Long-term inhalation of coal-rock dust at 1–3 weeks of seeding triggers adaptive mechanisms in the liver in the form of increased functional activity of cells, formation of double-core hepatocytes, activation of immunocompetent cells and endotheliocytes, ensuring the preservation of the parenchyma and the general morphostructure of the organ until the 12th week of the experiment. Exposure to sodium fluoride leads to early disruption of liver compensatory mechanisms and the development of dystrophic changes in the parenchyma with the formation of necrosis foci as early as the 6th week of the experiment.Conclusions. The study of mechanisms for compensating the liver structure in conditions of long-term exposure to coal-rock dust and sodium fluoride, as well as processes that indicate their failure, and the timing of their occurrence, is of theoretical and practical importance for developing recommendations for the timely prevention and correction of pathological conditions developing in employees of the aluminum and coal industry.The authors declare no conflict of interests.

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