Neonatal neuronal apoptosis after betamethasone administration in pregnant Wistar rats.
OBJECTIVE
To analyze the apoptosis of cortical and hippocampal neurons in newborn following the intramuscular administration of betamethasone in pregnant Wistar rats.


METHODS
Betamethasone or placebo was administered to 10 pregnant rats. Subsequently, 98 newborns were analyzed in three different groups: therapeutic dose (TD, 20 mg/kg), triple therapeutic dose (3TD, 60 mg/kg), and nine times TD (9TD, 180 mg/kg). Forty-four newborns were injected with placebo (control subjects--CTR). Neuronal apoptosis was measured by immunofluorescence using the TUNEL assay. The one-way analysis of variance, Tukey-Kramer (parametric) test and Kruskal-Wallis (non-parametric) test were used for statistical analysis.


RESULTS
The CA1 area of the hippocampus of TD and 3TD groups showed significant differences from that of the CTR group (p < 0.001). Compared to the CTR group, there was increased neuronal apoptosis in the dentate gyrus (DG) of animals in TD and 3TD groups (p < 0.0001). There were no significant differences in CA2 and CA3 regions as well as in amygdala and cortex.


CONCLUSIONS
Prenatal administration of betamethasone leads to significant changes in neuronal apoptosis in CA1 and DG regions.
a Department of Obstetrics, Fetal Medicine Discipline and.
Marcelo Santucci
MS
França
a Department of Obstetrics, Fetal Medicine Discipline and.
Antonio Fernandes
AF
Moron
a Department of Obstetrics, Fetal Medicine Discipline and.
Edward
E
Araujo Júnior
b Department of Physiology, Division of Neurophysiology, Paulista School of Medicine , Federal University of São Paulo (EPM-UNIFESP) , São Paulo , SP , Brazil.
Marcelo
M
Avedissian
a Department of Obstetrics, Fetal Medicine Discipline and.
David Baptista Silva
DB
Pares
a Department of Obstetrics, Fetal Medicine Discipline and.
Luciano Marcondes Marchado
LM
Nardozza
b Department of Physiology, Division of Neurophysiology, Paulista School of Medicine , Federal University of São Paulo (EPM-UNIFESP) , São Paulo , SP , Brazil.
Carolina Barros
CB
Jaqueta
b Department of Physiology, Division of Neurophysiology, Paulista School of Medicine , Federal University of São Paulo (EPM-UNIFESP) , São Paulo , SP , Brazil.
Luiz Eugênio Araujo Moraes
LE
Mello
D000818:Animals; D000831:Animals, Newborn; D017209:Apoptosis / Q000187:drug effects*; D001623:Betamethasone / Q000008:administration & dosage / Q000494:pharmacology*; D002452:Cell Count; D018891:Dentate Gyrus / Q000166:cytology / Q000187:drug effects; D005260:Female; D006624:Hippocampus / Q000166:cytology / Q000187:drug effects; D008297:Male; D009474:Neurons / Q000187:drug effects* / Q000502:physiology; D011247:Pregnancy; D011297:Prenatal Exposure Delayed Effects / Q000139:chemically induced / Q000503:physiopathology; D051381:Rats; D017208:Rats, Wistar
D001623:Betamethasone
Betamethasone; TUNEL assay; Wistar rats; immunofluorescence; neonatal neuronal apoptosis; pregnancy