Elastic Properties of the Cell Surface and Metabolic Profile of an Embryonic Primary Mixed Culture of Hippocampal Neurons under Conditions of P2X3 Receptor Blockade

P2X3-receptors localized in the hippocampus participate inthe transmission of excitation and the formation of synaptic plasticityunderlying learning and memory. P2X3-receptors are of great importancein the occurrence of neuropathic pain in epilepsy, acute and inflammatorypain of various genesis and localization as well as in the activationand growth of nerves after traumatic brain injury. The aim of thestudy was to study the elastic properties of the surface and themetabolic profile of neurons in an embryonic primary mixed hippocampalculture under P2X3-receptor blockade. The study was performed ona primary mixed culture of hippocampal neurons obtained from CD1mice on the 18th day of gestation (E18). The highly selective blocker5-(5-iodo-2-isopropyl-4-methoxyphenoxy)pyrimidine-2.4-diamine monochloridesalt was selected as a P2X3-receptor blocker. To assess the elasticproperties of neurons Young’s modulus that characterizes the rigidityof the cell surface was measured. Measurements on an atomic forcemicroscope applying a load in 25 local areas of the cell surfacewere performed. At each point, the force curves of the cantileverapproach and retraction were recorded with subsequent calculationof Young’s modulus. The metabolic profile of the neuroglial culturein Energy Phenotype test on a Seahorse HS mini cell metabolism analyzer(USA) was studied. The Young’s modulus of the cell surface of neuronsin the control was in the range from 6.8 ± 0.1 to 9.7 ± 0.2 kPa,and under the action of the P2X3-receptor blocker in the range from3.1 ± 0.1 kPa to 8.5 ± 0.1 kPa. Under the conditions of P2X3-receptorblockade on the 5th day of differentiation the Young's modulus ofthe cell surface was reduced by 62% (p <0.05), on the 8th day it increased by 22% (p <0.05) and by the 11th day it decreased by 16.7% (p < 0.05) compared to the control.Aerobic respiration was characteristic of the embryonic hippocampalculture both in the control and with the P2X3-receptor blockade. Consequently,the blockade of the P2X3-receptor did not affect the metabolic profileof the E18 hippocampal culture. The obtained data indicate the directparticipation of the P2X3-receptor in the formation of biomechanicalproperties of the cell surface in the processes of differentiationand signal transduction. It is possible, that the blockade of theP2X3-receptor will be one of the promising molecular targets thatcan reduce neuronal damage in brain injuries, neuroinflammation,hypoxia, and epilepsy. In addition, the study of the P2X3-receptorblockade can expand the fundamental understanding of the role ofthe purinergic signaling system in the formation of complex neuronal morphologyat early stages of embryonic development under conditions of rapidexcitatory signal transmission mediated by the ATP molecule.