Biomedical subjects

I Valkounová

Publications and source records attributed to I Valkounová.

3 recordsLinked to original sources

PubMed2001

Excitability changes of cortical neurons during the postnatal period in rats exposed to prenatal hypobaric hypoxia.

Pregnant rats were exposed to intermittent hypobaric hypoxia (at a simulated altitude of 7000 m or 5000 m) and the excitability of cortical neurons of their pups was tested. Stimulation of the sensorimotor cortex of rats prenatally exposed to hypoxia shortened the duration of cortical afterdischarges in 12-day-old rats, but did not change the excitability in 25-day-old animals. Shortening of the first afterdischarge in 35-day-old rats but the prolongation of the first afterdischarge in adult rats (as compared to the duration of cortical afterdischarges in rats not exposed to prenatal hypoxia) were registered. The possible mechanisms of different excitability of cortical neurons in rats prenatally exposed to hypobaric hypoxia are discussed.

Altitude↗

PubMed2001

Carnitine pretreatment can partially change the excitability of the immature nervous tissue.

The possible protective action of L-carnitine on neuronal excitability was studied in 21-day-old male Wistar rats with implanted electrodes. Administration of L-carnitine did not change the elicitation and duration of the epileptic seizures (cortical afterdischarges, ADs) in rats under normobaric oxygen atmosphere conditions. However, in animals exposed to 30 min hypobaric hypoxia the duration of the ADs was shortened after the second, fourth and sixth stimulation (in comparison with the first evoked ADs) while carnitine-treated rats retained their neuronal excitability and the duration of ADs was shortened only after the third stimulation.

Animals↗

PubMed2001

Perinatal complication: hypoxic-ischemic encephalopathy.

The favourable development of foetus is connected with the sufficient oxygen requirement. The brain of the foetus is extraordinarily sensitive to the disorders of oxygen supply. Ischemic brain injury connected with perinatal asfyxia is a frequent cause of hypoxic encephalopathy. An increased tolerance of the brain could be achieved by using peptide grows factors, inhibition of nitric oxide or modifying the glutamate receptors activity. Cerebral hypoxia evolves mainly in the case interruption of the feto-placental circulation or cardiorespiratory failure in the neonate. For making the diagnosis of neonatal encephalopathy is important to determine clinical neurological and systemic deragements in the first few days of life. Assessment of prognosis is generally based on a combination of clinical features and abnormalities of examination methods (electroencephalography, computer tomography).

Asphyxia Neonatorum↗