Ontogenetic Characteristics of Behavior in Rats Subjected to Hypoxia on Day 14 or Day 18 of Embryogenesis

摘要

Physiological development, motor activity, and cognitive functions were studied in ratsubjected toacute normobaric hypoxic hypoxia (3 h at an 02 concentration of 7%) at different stages oUnbryogen-esis (days E14 or El 8). Prenatal hypoxia was found to lead to delays in physiological development andthe establishment of motor behavior during the first month of postnatal ontogenesis. These changes weremore marked in rats subjected to hypoxia on day 14 of intrauterine development and disappeared withage. In adult rats, regardless of the timing of exposure to hypoxia (E14 or El 8), learning ability wasdegraded and long-term and short-term memory were impaired. These results suggest that exposure tothe pathogenic factor during the main period of neuroblast generation and migration (E14) was signifi-cant both for physiological development and the establishment of motor behavior in the animals and forthe execution of the cognitive functions of the brain, while exposure during the period at which matura-tion and differentiation processes dominate in the brain (El 8) was more significant in relation to the exe-cution of cognitive functions.