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arXiv · 2308.03778

Role of water in physics of blood and cerebrospinal fluid

Abstract

Known physical mechanisms of temperature dependence anomalies of water properties were used to explain the regularities in temperature dependence (TDs) of dynamic, electrical and optical characteristics of biological systems. The dynamics of hydrogen bonds in bulk and hydrated water affected the activation energies TDs of ion currents of voltage-dependent channels that regulate signaling and trophic bonds in the neuropil of the cortical parenchyma. The physics of minimizing the TD of the isobaric heat capacity of water made it possible to explain the stabilization and functional optimization of the thermodynamics of eyeball fluids at 34.5 C and the human brain during sleep at 36.5 C. At these temperatures, the thermoreceptors of the cornea and the cells of the ganglionic layer of the retina, through connections with the suprachiasmatic nucleus and the pineal gland, switch the circadian rhythm from daytime to nighttime. The phylogenesis of the circadian rhythm was reflected in the dependence of the duration of the nighttime sleep of mammals on the diameter of the eyeball and the mass of the pineal gland. The activity of all the nerves of the eyeball led to the division of the nocturnal brain metabolism into NREM and REM phases. These phases correspond to two modes of the glymphatic system - electrochemical and dynamic. The first is responsible for the relaxation processes of synaptic plasticity and chemical neutralization of toxins with the participation of water and melatonin. Rapid eye movement and an increase in cerebral blood flow in the second mode increase water exchange in the parenchyma and flush out toxins into the venous system. Electrophysics of clearance and conductivity of ionic and water channels of membranes of blood vessels and astrocytes modulate oscillations of polarization potentials of water dipole domains in parietal plasma layers of arterioles and capillaries.

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Alexander Kholmanskiy. 2023-08-01. Role of water in physics of blood and cerebrospinal fluid. https://arxiv.org/abs/2308.03778

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