Аннотация:Perinatal hypoxic-ischemic brain damage is a major cause
of acute mortality and chronic neurologic morbidity in
infants and children. The severity of the resulting brain
damage is dependent on the intensity, duration and time
of the hypoxia. Obstetric complications such as prolonged
hypoxia is suspected to increase the risk for such mental
disorders as schizophrenia, epilepsy, deficit hyperactivity
disorder, mental retardation. Animal studies are quite
important in providing mechanisms underlying perinatal
hypoxia brain damages. One of the most perspective
correction method is the use of regulatory peptides, for
example Semax (ACTH4-7 – PGP), the well known
antihypoxic and nootropic drug.
The white rat females were subjected to acute hypobaric
hypoxia on the 9–10th day of pregnancy that corresponding
to the period of main organism’s systems formation including
the nervous one. The morphometric characteristics of
newborns were registered from the 1st to the 60th day
of life. Besides, the spontaneous behavioral activity and
the anxiety level were investigated in 60-day-old rat pups
using hole board and elevated X-maze tests while the
bioamines levels in brain stem and cerebral cortex as
well as morphometric analysis of neuronal populations
in CA1 and CA4 hyppocampal areas were determined
using fluorescent and hystological methods, respectively.
The descendants from females, subjected to acute
hypoxia, were born with low birth weight which remained
significantly lower compared to control for at least 60
days of their postnatal period. Besides, 60-day-old rats of
both sexes demonstrated hypoactivity and the decrease of
orientative-training reactions whereas young females were
also less anxious. Thus, the antenatal hypoxia induced the
noticeable behavioral disorganization.
The behavioral effects were in good agreement with
observed biochemical and hystological changes. Thus,
the general density of neuronal populations in CA1 and
CA4 hyppocampal areas was decreased either in males
(9,7% and 16,7%, respectively) or in females (9,1%
and 11%, respectively), surviving antenatal hypoxia. The
total number of free cells in both areas didn’t change
while the number of cells with satellite glia decreased
by 29,6% in males and 12,6% in females. At the same
time, the number of morphologically changed cells in CA1
hyppocampal area was significantly increased in males
remained unchanged in females.
The changes in bioamines levels were also more
expressed in males. Thus, NE and DA levels were
enhanced both in brain stem and cerebral cortex in males
whereas females demonstrated the significant increase of
brain stem DA level only.
The intranasal administration of Semax, 0.01 mg/kg to
60-day-old rat pups eliminated mentioned above hypoxia
influences on bioamines balance and diminished the
antenatal hypoxia induced behavioral disorganization.
The antenatal hypoxia seems to contribute to the
development of severe neurological disturbances, especially expressed in 60-day-old male rats. In some cases
hypoxia induced influences can be eliminated by intranasal
administration of Semax.