Early postnatal hypoxia induces long-term changes in the dopaminergic system in rats.
A rat model of a mild, chronic, early postnatal hypoxia, characterized by long-term consequences in the behavioural outcome, was used to study long-term consequences in the dopaminergic system. Exposure of newborn rats to an early postnatal hypoxia (hypobaric hypoxia, 11 kPa pO2 in the inspiratory air, 2nd-10th day of life, 10 hours daily) brings about the following lasting neurochemical changes: an increased stimulated dopamine release rate from striatum slices by about 30%, an increased low affinity, high capacity dopamine uptake into striatum synaptosomes by about 100%. The critical period to produce an increased release rate of dopamine was estimated as day 2-6 postnatally. There are no long-term changes in the concentration of dopamine and its metabolites and in the tyrosine hydroxylase activity in consequences of this early postnatal hypoxia. Treatment of newborn animals with L-DOPA (10-50 micrograms/g body weight) previous to hypoxia normalizes the DA release rate.
Gross
J
J
Institute of Pathological and Clinical Biochemistry, Medical School (Charité), Humboldt University, Berlin, Federal Republic of Germany.
Lun
A
A
Berndt
C
C
D000818:Animals; D000831:Animals, Newborn / Q000502:physiology; D001362:Avoidance Learning / Q000502:physiology; D001522:Behavior, Animal / Q000502:physiology; D002395:Catecholamines / Q000378:metabolism; D003342:Corpus Striatum / Q000378:metabolism; D004298:Dopamine / Q000378:metabolism / Q000502:physiology*; D000860:Hypoxia / Q000473:pathology* / Q000523:psychology; D007980:Levodopa / Q000494:pharmacology; D011188:Potassium / Q000494:pharmacology; D051381:Rats; D017208:Rats, Wistar; D013574:Synaptosomes / Q000187:drug effects / Q000378:metabolism; D014446:Tyrosine 3-Monooxygenase / Q000378:metabolism
D002395:Catecholamines; D007980:Levodopa; D014446:Tyrosine 3-Monooxygenase; D011188:Potassium; D004298:Dopamine