[Specificity of ontogenic development of behavior of rats subjected to prenatal hypoxia on the 14-th or 18-th days of embryogenesis].

: Physiological development, movement activity and cognitive functions of rats subjected to acute normobaric hypoxia (7% O2 during 3 h) at different days of embryogenesis (E14 or E18) were investigated. It was found that prenatal hypoxia led to a delay in physiological development and formation of motor behavior during the 1st month after birth. Differences observed were more pronounced in rats subjected to hypoxia on the 14th day of intrauterine development but disappeared with maturation of the animals. Independently of the day of the hypoxic episode (E14 or E18), learning ability and memory (long-term and short-term) impaired in all adult rats. The findings suggest that the exposure to hypoxia at the stage of predominant generation and migration of neuroblasts (E14) is disruptive for physiological development, formation of motor behavior and cognitive function, whereas the exposure to hypoxia at the stage of predominant cell maturation (E18) is in general more disruptive for cognitive functions.