RF Safe

Changes in numbers and size of synaptic vesicles of cortical neurons induced by exposure to 835 MHz RF EMF

2017 · Harm · Low evidence

← Research stream
HarmLow evidencePaper 2203

C57 BL/6 mice exposed to 835 MHz RF-EMF (4.0 W/kg SAR, 5 h daily) showed a significant decrease in synaptic vesicle density in presynaptic boutons of cortical neurons. Synapsins I/II gene and protein expression were also significantly decreased in cortical ne…

Study snapshot

Publicationmanual · 2017
Study typeanimal
Reported directionHarm
Evidence ratingLow

Abstract

Changes in numbers and size of synaptic vesicles of cortical neurons induced by exposure to 835 MHz RF EMF Kim JH, Kim HJ, Yu DH, Kweon HS, Huh YH, Kim HR. Changes in numbers and size of synaptic vesicles of cortical neurons induced by exposure to 835 MHz radiofrequency-electromagnetic field. PLoS One. 2017 Oct 18;12(10):e0186416. Abstract We studied the effects of radiofrequency electromagnetic fields (RF-EMFs) exposure on neuronal functions of mice. Particularly, we focused on RF-EMF effects on synaptic vesicles (SVs), which store neurotransmitters at axon terminals or synaptic boutons. C57 BL/6 mice were exposed to 835 MHz RF-EMF (4.0 W/kg SAR, for 5 h daily) and alterations in SVs at presynaptic terminals in the cerebral cortex were determined. Ultrastructure of randomly selected cortical neurons was observed using typical electron microscopy and bio-high voltage electron microscopy (Bio-HVEM) methods, which enable the estimation of the numbers and size of SVs. The density of the SVs (number /10 μm2 or 40 μm3) was significantly decreased in the presynaptic boutons of cortical neurons after RF-EMF exposure. Furthermore, qPCR and immunoblotting analyses revealed that the expression of synapsins I/II (Syns I/II) genes and proteins were significantly decreased in the cortical neurons of RF-EMF exposed mice. The present study suggested that alteration of SVs and Syn levels may result in alterations of neurotransmitters in the cerebral cortex following RF-EMF exposure. ncbi.nlm.nih.gov

Machine Enhanced Logic

AI evidence extraction

Structured fields below were generated from the paper’s abstract and metadata to make the evidence easier to inspect. Automated extraction may be incomplete or incorrect; verify important details against the original paper.

Study typeanimal
Effect directionharm
PopulationC57 BL/6 mice
Sample sizeNot supplied
ExposureRF · 835 MHz · 4 W/kg · 5 h daily
Evidence strengthLowConfidence: 74% · Peer reviewed: yes

Main findings

C57 BL/6 mice exposed to 835 MHz RF-EMF (4.0 W/kg SAR, 5 h daily) showed a significant decrease in synaptic vesicle density in presynaptic boutons of cortical neurons. Synapsins I/II gene and protein expression were also significantly decreased in cortical neurons of exposed mice.

Outcomes measured

  • Synaptic vesicle density (number/10 μm2 or 40 μm3) in presynaptic boutons of cortical neurons
  • Synaptic vesicle number and size (electron microscopy/Bio-HVEM estimation)
  • Synapsins I/II gene expression (qPCR)
  • Synapsins I/II protein expression (immunoblotting)

Limitations

  • Sample size not reported in the provided abstract/metadata
  • Exposure duration in days/weeks not specified beyond '5 h daily'
  • Functional/behavioral outcomes not reported; findings are ultrastructural and molecular
View raw extracted JSON
{
  "study_type": "animal",
  "exposure": {
    "band": "RF",
    "source": null,
    "frequency_mhz": 835,
    "sar_wkg": 4,
    "duration": "5 h daily"
  },
  "population": "C57 BL/6 mice",
  "sample_size": null,
  "outcomes": [
    "Synaptic vesicle density (number/10 μm2 or 40 μm3) in presynaptic boutons of cortical neurons",
    "Synaptic vesicle number and size (electron microscopy/Bio-HVEM estimation)",
    "Synapsins I/II gene expression (qPCR)",
    "Synapsins I/II protein expression (immunoblotting)"
  ],
  "main_findings": "C57 BL/6 mice exposed to 835 MHz RF-EMF (4.0 W/kg SAR, 5 h daily) showed a significant decrease in synaptic vesicle density in presynaptic boutons of cortical neurons. Synapsins I/II gene and protein expression were also significantly decreased in cortical neurons of exposed mice.",
  "effect_direction": "harm",
  "limitations": [
    "Sample size not reported in the provided abstract/metadata",
    "Exposure duration in days/weeks not specified beyond '5 h daily'",
    "Functional/behavioral outcomes not reported; findings are ultrastructural and molecular"
  ],
  "evidence_strength": "low",
  "confidence": 0.74,
  "peer_reviewed_likely": "yes",
  "keywords": [
    "835 MHz",
    "RF-EMF",
    "SAR 4.0 W/kg",
    "mouse",
    "cerebral cortex",
    "synaptic vesicles",
    "presynaptic boutons",
    "electron microscopy",
    "Bio-HVEM",
    "synapsin I",
    "synapsin II",
    "qPCR",
    "immunoblotting"
  ],
  "suggested_hubs": [
    {
      "slug": "animal-studies",
      "weight": 0.9,
      "reason": "Experimental RF-EMF exposure study in mice assessing neuronal ultrastructure and synaptic proteins."
    }
  ]
}
AI can be wrong. Always verify against the paper.

AI-extracted fields are generated from the abstract and metadata and may be incomplete or incorrect. This material is for informational purposes and is not medical advice.

Identifiers and source

DOI: Not supplied
PubMed: Not supplied

Read the original paper →

Related papers

← Back to the Research Library