Mechanisms of the action of endogenous electrotonic influences and exogenous factors on biological rhythms of neurons

• Published in: Cardiometry 2018-05 (12), p.39-53
• Main Authors: Orlov, Valery I., Sukhov, Aleksandr G., Kit, Oleg I., Shikhlya­rova, Alla I., Rudenko, Mikhail Y., Kirichenko, Evgeniya Y., Fillipova, Svetlana Y., Pashintsev, Sergey G.
• Format: Article
• Language: English
• Subjects: Biological rhythms; Neurons
• ISSN: 2304-7232; 2304-7232
• DOI: 10.12710/cardiometry.2018.12.3953

Subjects of our experimental studies were neurons in the snail Helix Pomatia, from which continuous intracellular recordings according to our specific microelectrode recording technique were produced. We have carried out original investigations of the processes of control and regulation of endogenous biological rhythms of neurons, observing them both under their background activity (free of stimulation) and under the action of the exogenous factors within a chronic experiment, which involved continuous recordings of activity from the neurons that covered periods from 50 to 60 hours, with an incubated ganglion cell life span up to four 24-hour days. In the neurophysiological experimental studies with recordings of intracellular activity of the identified CNS neurons in the Roman snail Helix Pomatia, we conducted a research into identification of a contribution of potential-dependent ion (K+, Ca2+, Na+) channels to formation of pacemaking oscillatory activity of the neurons and an interplay of the AP generation loci unequally or irregularly spaced. It has been shown that it is possible to activate at the same time 2–3 individual loci of generation of the Na+ spikes, differing in their amplitudes, which appear at different segments of the axo-dendritic axis of the neurons in the snail Helix Pomatia. We undertook an ultra-structural morphological examination of the states of the axotomized neurons in the snail Helix Pomatia, followed by an analysis of the neuro-glial relations at the microelectrode recording locus. Specificity of responses of the axotomized neurons to exposures to blue, red and white light have been discovered and analyzed by us. Aim Our experiments with long-term intracellular recordings from the neurons in snail Helix Pomatia were aimed at an identification of specific features of the action of endogenous electrotonic influences and exogenous factors on biological rhythms of a neuron. The main goals of our experimental studies were as follows: 1. Neuromorphological examinations of the state of the neurons in the snail Helix Pomatia during long-term intracellular recordings of the background biological rhythms versus those upon light exposure & broad-band electromagnetic stimulation. 2. Intracellular recording data analysis of the background pacemaker genome-regulated biological rhythms of the neurons in the snail Helix Pomatia under the conditions of the normal activity versus epyleptiform activity in case of channelopathies. 3. Intracellula