The molecular mechanism of dark noise in rod photoreceptors

The molecular mechanism of dark noise in rod photoreceptors skin#

Phosphenes, retinal discrete dark noise, negative afterimages and retinogeniculate projections: A new explanatory framework based on endogenous ocular luminescence. Salari V., Scholkmann F., Vimal R.L.P., Csaszar N., Mehdi Aslani M., Bokkon I. The Physical Mechanism for Retinal Discrete Dark Noise: Thermal Activation or Cellular Ultraweak Photon Emission? PLoS ONE. Salari V., Scholkmann F., Bokkon I., Shahbazi F., Tuszynski J. Retinal phosphenes and discrete dark noises in rods:ДЄ new biophysical framework. Chemistry and metabolism of lipids in the vertebrate retina. An overview of lipid peroxidation with emphasis in outer segments of photoreceptors and the chemiluminescence assay. Peroxy-radical mediated chemiluminescence: mechanistic diversity and fundamentals for antioxidant assay. 2011.ДЇedorova G.F., Trofimov A.V., VasiilвЂ™ev R.F., Veprintsev T.L. Chemistry and biology of reactive oxygen species in signaling or stress responses. Mitochondrial formation of reactive oxygen species. Monitoring low-density lipoprotein oxidation by low-level chemiluminescence. Visible-range low-level chemiluminescence in biological systems. Redox mechanisms in hepatic chronic wound healing and fibrogenesis. Measuring the human ultra-weak photon emission distribution using an election-multiplying, charge-coupled device as a sensor. Ortega-Ojeda F., Calcerrada M., Ferrero A., Campos J., Garcia-Ruiz C. Ultra-weak photon emission from biological samples: Definition, mechanisms, properties, detection and applications.

The molecular mechanism of dark noise in rod photoreceptors skin#

Ultraweak photon emission induced by visible light and ultraviolet A radiation via photoactivated skin chromophores: in vivo charge coupled device imaging. Biophotons as neural communication signals demonstrated by in situ biophoton autography. Lecture of 1953 transcribed by R.N.Hall and published in Physics Today. Revisiting the mitogenetic effect of ultra-weak photon emission. Das Cornealepithel as Detector and Sender mitogenetischer Strahlung. Physicalisches Гјber mitogenetische Strahlen. Die Natur des spezifischen Erregers der Zellteilung. Thus, the new explanatory framework for all visual phenomena based on UPE should be discarded in its entirety. All other sorts of phosphenes attributed to UPE cannot be produced by biophotons since it is known for at least 200 years that the phosphenes are seen in daylight, that is, at the intensities billions of times brighter than the intensity of UPE. Besides, the background light necessary to produce a negative afterimage is actually supplied by the ambient light that passes into the eye through closed lids. UPE also cannot be a source of afterimages because its intensity is far too low. Yet its intensity is two orders of magnitude below the dark-adapted visual threshold, and over 100 times smaller than necessary to generate the photoreceptorsвЂ™ dark noise. Experiments show that the retina in complete darkness indeed emits an extremely low level of bioluminescence. It is concluded that the outer segments of retinal photoreceptors provide an excellent substrate for LPO thus being a good candidate for UPE production. In the paper, the biochemical mechanism of biophotonsвЂ™ generation is briefly explained. The new framework provides a unifying explanation for all the phenomena that are suggested to be a perception of biophotons (ultra-weak photon emission, UPE) that are generated mostly by lipid peroxidation (LPO) during routine cellular metabolism. Such a link appears to be the manifestation of intrinsic chromophore features associated with the existence of a conical intersection between its ground and excited states.The review considers modern un-orthodox ideas on the origin of visual phenomena of apparently various nature (photoreceptorsвЂ™ dark light, negative afterimages, and various sorts of phosphenes such as electrophosphenes, magnetophosphenes, radiation phosphenes, and mechanophosphenes).

The transition state mediating thermal activation has the same electronic structure as the photoreceptor excited state, thus creating a direct link between lambda(max) and k. Here we show that a quantum chemical model of the bovine rod pigment provides a molecular-level understanding of the Barlow correlation. Although the mechanism of such a process is under debate, the observation of a relationship between the maximum absorption wavelength (lambda(max)) and the thermal activation kinetic constant (k) of different visual pigments (the Barlow correlation) indicates that the thermal and photochemical activations are related. Their origin is attributed to a thermal, rather than photochemical, activation of the transduction cascade. Abstract : Spontaneous electrical signals in the retina's photoreceptors impose a limit on visual sensitivity.