The effect of hypoxia induction at parturition on hyperthermia seizure severity, cognition, and motor coordination in rats

Hypoxia is a common stressor during childbirth, while hyperthermia-induced seizures are prevalent in infancy and childhood. This study aims to investigate the impact of hypoxia induction at parturition on the severity of hyperthermia seizures, as well as cognition and motor coordination in rats.

In this experimental study, 28 male Wistar rats were utilized. Four groups (7 rats each) included: control, hyperthermia (15 minutes of exposure to hot air at 41°C), hypoxia (7% oxygen and 93% nitrogen for 1 hour), and hypoxia combined with hyperthermia. We evaluated the number of tonic-clonic seizures and seizure threshold. Behavioral assessments in adult male offspring were conducted using new object recognition, open field, rotarod, inverted grid, and parallel bar tests.

In the hyperthermia + hypoxia group, the number of tonic-clonic seizures increased while the seizure threshold decreased (P < 0.05). Cognition in adult rats from the hypoxia + hyperthermia group was significantly impaired compared to the control group (P < 0.001). The distance traveled and speed in the open field (P<0.01), and balance on the rotarod rod (P<0.001), were significantly reduced in the hypoxia + hyperthermia group compared to controls. In the inverted grid and parallel bar tests, the duration of balance maintenance was significantly shorter in the hyperthermia + hypoxia group compared to controls (P < 0.01).

The findings of this study indicate that hypoxia at parturition leads to increased seizure activity in hyperthermic rats and results in behavioral disturbances in adulthood.