Experimental modeling of acute perinatal hypoxia induces disturbances insensorimotor functions and physical status of rat offspring

Abstract

Relevance. Perinatal hypoxia is defined as a systemic oxygen deficiency in the fetus or newborn, which determines the development of a wide spectrum of short-term and delayed negative medical consequences. The aim of this work was to establish the patterns of somatic and sensorimotor development disorders in the offspring of rats that underwent perinatal hypoxia.
Materials and methods. The study was conducted on Wistar rats (parental stock: 30 females, 10 males) randomly divided into two equal groups. The offspring of the first group developed under normoxic conditions (control). On the second postnatal day (P2), the offspring of the second group were subjected to a session of acute normobaric hypoxia (ANH) to model a state homologous to human preterm pregnancy. In early ontogenesis, a dynamic assessment of the physical and unconditioned reflex status of the animals was performed.
Results. A pronounced sex-dependent nature of the ANH-induced impairments was verified. In females of the experimental group, prolonged inhibition of somatic growth (body weight lag) was recorded, combined with delayed maturation of the cliff avoidance reflex, muscle strength deficit, and impaired dynamic balance on a rotating cylinder. In contrast, the neurological deficit in males was isolated and manifested as a delay in the execution of the surface righting reflex.
Conclusion. ANH experienced in the early neonatal period triggers a sex-specific delay in neurosomatic development in rats. Extrapolation of experimental data opens new possibilities for precise modeling of perinatal hypoxia outcomes in humans.