Behavioral and neuroanatomical effects on exposure to White noise in rats

Zhvania, Mzia G; Gogokhia, Nino; Tizabi, Yousef; Japaridze, Nadezhda; Pochkidze, Nino; Lomidze, Nino; Rzayev, Fuad; Gasimov, Eldar

doi:10.1016/j.neulet.2020.134898

Cited by 16 publications

(13 citation statements)

References 22 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Conventional EM technique, described in our earlier studies was used (Lobzhanidze et al, 2019(Lobzhanidze et al, , 2020Zhvania et al, 2015Zhvania et al, , 2020. Briefly, after pentobarbital injection (100 mg/kg), four animals from each age group underwent transcardiac perfusion with ice cold heparinized 0.9% NaCl, followed by 500 ml of 4% paraformaldehyde and 2.5% glutaraldehyde in 0.1 M phosphate buffer, pH 7.4, at a perfusion pressure 120 mmHg.…”

Section: Electron Microscopic (Em) Analysismentioning

confidence: 99%

Age‐related behavioral and ultrastructural changes in the rat amygdala

Lomidze¹,

Zhvania²,

Tizabi

et al. 2020

Developmental Neurobiology

Self Cite

View full text Add to dashboard Cite

Although the relationships between brain structure and emotions may alter across the life span, this relationship is of particular importance during aging when significant alterations in emotions may be manifested. Understanding the structural–behavioral relationship could not only provide a neurobiological basis of these changes, but could also suggest potential intervention. Since anxiety is commonly observed in aging population, we undertook this study to determine the extent of this behavioral manifestations as well as the associated ultrastructural changes in the amygdala. Rats of various age groups, adolescent, adult, and aged were tested for anxiety‐like behavior and the ultrastructure/presynaptic architecture of the central nucleus of amygdala (CNA) were evaluated using transmission electron microscopy (EM). Aged rats were consistently more anxious than the other groups as evidenced by their scores in the elevated plus maze. Morphometric EM analysis of axodendritic synapses revealed that the aged rats had a lower presynaptic area as well as number of synapses, but unexpectedly a higher number of presynaptic mitochondria in CNA. Since presynaptic mitochondria are known to provide the energy for neurotransmission, it may be concluded that compensatory mechanisms are still operational during aging, and hence, may be a target for therapeutic intervention at this stage of life span.

show abstract

Section: Electron Microscopic (Em) Analysismentioning

confidence: 99%

Age‐related behavioral and ultrastructural changes in the rat amygdala

Lomidze¹,

Zhvania²,

Tizabi

et al. 2020

Developmental Neurobiology

Self Cite

View full text Add to dashboard Cite

show abstract

“…Present study is the part of our broad investigation of presynaptic architecture in different mammals under various physiological and pathological conditions. [ 19 20 21 31 32 ] In the present study, we assess the size of synaptic vesicles in the subdivision of inferior colliculus, which receives the projections predominantly from cochlear nucleus and the part of lateral lemniscus. [ 23 24 25 ] The majority of these projections (∼60%) have large axon terminals and made asymmetric excitatory synapses with spherical synaptic vesicles.…”

Section: Discussionmentioning

confidence: 99%

“…Technical approach was described in our recent study. [ 31 32 ] Briefly in order to determine the changes in the diameter in both docked and undocked synaptic vesicles, on electron micrographs the 250 axon endings from control animals and 250 endings from noise-exposed animals (50 endings from each cat) were outlined. The tracings of axon terminals were scanned, using the scan plug-in for Adobe Photoshop CS3 and saved as 150 dpi tiff files.…”

Section: Methodsmentioning

confidence: 99%

Electron Microscopy Demonstrating Noise Exposure Alters Synaptic Vesicle Size in the Inferior Colliculus of Cat

et al. 2021

View full text Add to dashboard Cite

Context: White noise is known to have detrimental effects on different brain regions, especially auditory regions, including inferior colliculus. Although the basis for such alterations has been hypothesized to result from abnormalities in neurotransmitter release, the mechanism is unclear. The final step in neurotransmission is the docking and transient fusion of synaptic vesicles at the base of cup-shaped lipoprotein structures called porosomes at the presynaptic membrane and the consequent release of neurotransmitters. Earlier studies in cat brain document altered morphology of the secretory portal the porosome at nerve terminals in the inferior colliculus following white noise exposure. The current study was performed to test the hypothesis of possible changes to synaptic vesicle size in the colliculus, following white noise exposure. Material and Methods: Electron microscopic morphometry of synaptic vesicles size in axo-dendritic synapses at the colliculus region of the cat brain was performed. Results: We report, for first time, decreased size of both docked and undocked vesicles in high-intensity white noise-exposed animals. In both control and experimental animals, docked vesicles are demonstrated to be smaller than undocked vesicles, suggesting fractional discharge of vesicular contents via porosome-mediated kiss-and-run mechanism. Conclusion: These studies advance our understanding of neurotransmitter release and the impact of white noise on brain function.

show abstract

“…For EM study, four animals from each age group that were behaviorally tested in MBM, were randomly selected for EM evaluation. Conventional EM technique, described in our earlier studies was used (Lobzhanidze et al., 2019, 2020; M. G. Zhvania et al., 2015; M. Zhvania et al., 2020). Briefly, after an overdose of sodium pentobarbital (200 mg/ml dissolved in 10% ethanol), animals underwent transcardiac perfusion using ice cold heparinized 0.9% NaCl, followed by 500 ml of 4% paraformaldehyde and 2.5% glutaraldehyde in 0.1 M phosphate buffer, pH 7.4, at a perfusion pressure of 120 mm Hg.…”

Section: Methodsmentioning

confidence: 99%

“…The learning paradigm was evaluated on 12 animals from each age group, in a modified radial arm maze—multi‐branch maze (MBM), during light phase (09.00 a.m.–12.00 p.m.), as detailed previously (Lobzhanidze et al., 2020; M. Zhvania et al., 2020). The apparatus (45 × 8 × 30.5 cm) consisted of 10 equally spaced branches, mounted on props of 30 cm height.…”

Section: Methodsmentioning

confidence: 99%

Aging affects cognition and hippocampal ultrastructure in male Wistar rats

Lomidze

Zhvania

Tizabi

et al. 2021

Developmental Neurobiology

Self Cite

View full text Add to dashboard Cite

It is now well established that aging is associated with emotional and cognitive changes. Although the basis of such changes is not fully understood, ultrastructural alterations in key brain areas are likely contributing factors. Recently, we reported that aging‐related anxiety in male Wistar rats is associated with ultrastructural changes in the central nucleus of amygdala, an area that plays important role in emotional regulation. In this study, we evaluated the cognitive performance of adolescent, adult, and aged male Wistar rats in multi‐branch maze (MBM) as well as in Morris water maze (MWM). We also performed ultrastructural analysis of the CA1 region of the hippocampus, an area intimately involved in cognitive function. The behavioral data indicate significant impairments in few indices of cognitive functions in both tests in aged rats compared to the other two age groups. Concomitantly, a total number of presynaptic vesicles as well as vesicles in the resting pool were significantly lower, whereas postsynaptic mitochondrial area was significantly higher in aged rats compared to the other age groups. No significant differences in presynaptic terminal area or postsynaptic mitochondrial number were detected between the three age groups. These results indicate that selective ultrastructural changes in specific hippocampal region may accompany cognitive decline in aging rats.

show abstract

Behavioral and neuroanatomical effects on exposure to White noise in rats

Cited by 16 publications

References 22 publications

Age‐related behavioral and ultrastructural changes in the rat amygdala

Age‐related behavioral and ultrastructural changes in the rat amygdala

Electron Microscopy Demonstrating Noise Exposure Alters Synaptic Vesicle Size in the Inferior Colliculus of Cat

Aging affects cognition and hippocampal ultrastructure in male Wistar rats

Contact Info

Product

Resources

About