Volume 59, Nº 2 (2023)

Based on the analysis of extensive clinical, psychophysiological and experimental data, the author comes to the conclusion that the widespread idea of the cerebral information processing during sleep related to previous wakefulness and necessary for the formation of long-term memory and other cognitive resources of the brain is inapplicable. This hypothesis does not agree well with a wide range of data regarding both non-REM and REM sleep. The state of the cerebral cortex in non-REM sleep is more adequately described by the classical term “diffuse cortical inhibition.” As for REM sleep, here, too, the very intensive work of the brain does not play any adaptive role (at least for an adult organism) - information is processed, figuratively speaking, “idle”. All the vast experimental and clinical material accumulated in recent decades speaks in favor of the “ecological” hypothesis, which considers sleep as periods of “adaptive inactivity” of the body, increasing its survival in a hostile environment. The function of sleep, perhaps, consists in a radical restructuring of all waking reflexes for the normal course of such periods.

A search and identification of osmotically active proteins (OAP) in the composition of blood serum anodic fraction from Atlantic cod Gadus morhua were undertaken using polyacrylamide gel electrophoresis and MALDI mass-spectrometry. 17 OAP have been identified. According to the annotations of Gene Ontology for candidates, 13 OAP were classified as extracellular and 4 OAP- as intracellular proteins. The relative content of OAP in cod serum was ~50% of the total protein. Extracellular proteins apolipoproteins (in the composition of high-density lipoproteins) and hemopexin were dominated in OAP pool. Moreover, the relative content of ApoA-I was ~25% of the total serum protein. Of the intracellular proteins on the serum proteomic map, low molecular weight fragments of the myosin heavy chain were dominated. The results obtained are consistent with the provisions of the “albumin-free” hypothesis of capillary exchange, which considers multiple extracellular and intracellular proteins from different functional classes as osmotically active plasma proteins of “albumin-free” teleost fish.

Animal behaviors are often characterized by behavioral asymmetry, or lateralization, which is caused in part by the morphological asymmetry of the body and/or brain. To test the hypothesis that functional asymmetry of grooming is connected with morphological asymmetry of the antennae in American cockroach Periplaneta americana, we measured the length of the antennae, scapus diameter, pedicel diameter and length, and segment’s diameter and length. The data obtained indicate statistically significant differences: segment length is greater on the left antennae, and segment width is greater on the right antennae, except for a short region near the base. Correlation analysis revealed the following relationships: longer right antenna corresponds to more time spent cleaning it; scapus diameter larger on the right antenna correlates with antenna cleaning frequency; asymmetry of flagellum segments has no effect on cleaning asymmetry. Presenting sex pheromone at a suprathreshold dose increased asymmetry of antennal grooming, while asymmetry for leg grooming was generally unchanged. Thus, the asymmetry of antennal grooming, resulting at least in part from morphological asymmetry, significantly changes in the presence of a biologically important olfactory stimulus, the sex pheromone.

Microelectrode technique was used to study the responses of identified peptide-containing cells VD1 and RPaD2 within isolated CNS of Lymnaea stagnalis to long-lasting (not less 2 h) exposure in D-glucose (10 mM) containing solution. It has been established that electrical characteristics of RPaD2 membrane, compared to VD1, undergo significant changes under experimental hyperglycemia. Decrease of membrane resistance (R_m), accompanied by an increase of membrane capacitance (C_m) and time constant (τ_m), were observed. Despite the invariance of their firing rate, depolarization of VD1 membrane take place, while RPaD2 membrane potential did not vary significantly. Modifications in time-course, but not amplitude, of VD1 and RPaD2 action potentials were similar and resulted in increase of their main phases (rising, falling, undershoot) duration. It is assumed that “identity” in membrane electrical properties of Lymnaea’s CNS neurosecretory neurons (VD1/RPaD2) at hyperglycemia plays an adaptive role, aimed to overcome the possible desynchronization of their spike activity as a result of electrical decoupling, initiated by a high glucose content in intercellular space.