• Effects on the mitochondrial Krebs cycle increase production of intracellular adenosine triphosphate. Transmembrane transport through voltage-gated ion channels is dependent on adenosine triphosphate. Voltage-gated ion channels may be positively influenced by the presence of external current flow, enabling the configuration change that precedes ion flow.¹⁹
• Influence of extremely low-frequency electromagnetic fields has been demonstrated to have beneficial and therapeutic effects on voltage-gated calcium channels via influence on the G-protein channel through the nitric oxide-cyclic GMP–protein kinase pathway.²⁵
• Alteration in gene expression, such as upregulation of Bcl-2, ciliary neurotrophic factor, and brain-derived neurotrophic factor; downregulation of Bax; suppression or inhibition of inflammatory factors, such as IL-1β and TNF-α; and transcriptome changes in 490 genes have been identified, including neuroprotective genes, such as Bax or those that are part of the TNF family. Additionally, upregulation of intrinsic insulin-like growth factor-1 (Mueller cell activation and diffusion into the inner retina) was found.^9,10




• Increase in choroidal vessel blood flow in normal human subjects, measured in ten healthy subjects following TES using a laser speckle flowgraphy, showed that there was statistically significant increase in blood flow in the macular zone, which may account for the improvements in patients with ischemia.²⁶

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Noninvasive Electrical Stimulation Improves Photoreceptor Survival and Retinal Function in Mice with Inherited Photoreceptor Degeneration.
Invest Ophthalmol Vis. Sci. 2020 Apr 9;61(4):5 doi: 10.1167/iovs.61.4.5: PMID: 32271885; PMCID: PMC7401948