Comparative analysis of the effects of various stress factors at the stage of early organogenesis on heart rate variability in pregnant female rats and their offspring.

We studied changes in the autonomic balance of heart regulation (by the parameters of heart rate variability) in non-pregnant female rats and rats on the days 10-11 of pregnancy on the next day after stress provoked by acute hypobaric hypoxia, intermittent normobaric hypoxia, or immobilization. The same parameters were assessed in 36-day-old offspring. In non-pregnant rats, the intermittent hypoxia resulted in a shift of the autonomic balance of heart regulation towards activation of the parasympathetic nervous system; in pregnant females, immobilization led to a shift of the autonomic balance towards the sympathetic nervous system. In the offspring, the changes also depended on the type of stress.

Transgeneration effects of antenatal acute hypoxia during early organogenesis.

We studied the effect of acute hypobaric hypoxia in early organogenesis on physiological and behavioral parameters of second-generation albino rats. Antenatal acute hypoxia was followed by physical and sexual retardation, increase in the mortality rate, and behavioral changes in second-generation animals (hypoactivity of males and females on day 22 of life and hyperactivity of males on day 57 of life). Second-generation animals exhibited no gender differences in body weight and horizontal and vertical locomotor activity.

Effect of antenatal hypoxia on age-specific dynamics of ECG parameters and content of biogenic amines in the central nervous system.

We studied the effect of acute antenatal hypoxia during the stages of progestation and early organogenesis on some ECG parameters and level of biogenic amines in brain structures in rats. The effect of acute hypoxic exposure during the organogenesis period on the studied parameters was more pronounced than the effect of acute hypoxic exposure during the progestation period. The shift of the autonomic balance towards the sympathetic regulation of cardiac activity is linked with increased content of biogenic amines in the brain stem and cortical structures.

Peptidergic correction of behavior in adult progeny of albino rats exposed to acute hypoxia during early organogenesis.

Physical development, spontaneous behavior, and training capacity were evaluated in adult progeny of albino rats exposed to acute hypobaric hypoxia on days 9-10 of gestation, corresponding to the early organogenesis period. Prenatal hypoxia caused delayed behavioral disorders, which were more pronounced in females born from mothers with low resistance to hypoxia. Therapeutic intranasal administration of Pro-Gly-Pro peptide in a dose of 1 mg/kg to rat pups on days 13-15 of life completely prevented the negative consequences of acute prenatal hypoxia in adult females and leveled virtually all negative consequences, except delayed physical development, in males.

Effect of hypoxia during early organogenesis on cardiac activity and noradrenergic regulation in the postnatal period.

Cardiac activity in rats during the postnatal period was studied in vitro and in vivo after exposure of rat pups to antenatal acute hypobaric hypoxia at the stage of organogenesis (day 9-10 of gestation). Cultured cardiomyocytes from rat pups exposed to antenatal hypoxia were characterized by increased rate of contractions and decreased reactivity to norepinephrine. Heart rate elevation, predominance of sympathetic influences on cardiac activity, and significant increase in norepinephrine concentration in the cerebral cortex were found in freely moving animals exposed to antenatal hypoxia. Our results indicate that hypoxia at the stage of organogenesis modulated cardiac activity during the postnatal period, which manifested at the level of effector structures in the heart and activity of regulatory systems.

Acute hypoxia during organogenesis affects cardiac autonomic balance in pregnant rats.

Changes in ECG parameters were studied in pregnant rats exposed to acute hypobaric hypoxia during the period of organogenesis (gestation days 9 to 10). Rats with low, medium, and high tolerance to hypoxia exhibited pronounced autonomic nervous system imbalance, which become apparent as a loss of correlation between various parameters of ECG signals recorded at rest and during exposure to some stress factors existing under normal conditions.

The effects of ante- and postnatal hypoxia on the central nervous system and their correction with peptide hormones.

Ante- and postnatal hypoxia significantly worsened the postnatal development of animals. The posthypoxic behavioral model included hyperactivity and decreased learning ability, these being typical manifestations of attention deficit disorder. A peptide constellation prevented and significantly improved posthypoxic postnatal development and eliminated the majority of negative behavioral changes.