Neonatal neuronal apoptosis after betamethasone administration in pregnant Wistar rats

J Matern Fetal Neonatal Med. 2016;29(7):1089-93. doi: 10.3109/14767058.2015.1035639. Epub 2015 Apr 29.

Abstract

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.

Conclusion: Prenatal administration of betamethasone leads to significant changes in neuronal apoptosis in CA1 and DG regions.

Keywords: Betamethasone; TUNEL assay; Wistar rats; immunofluorescence; neonatal neuronal apoptosis; pregnancy.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Animals, Newborn
  • Apoptosis / drug effects*
  • Betamethasone / administration & dosage
  • Betamethasone / pharmacology*
  • Cell Count
  • Dentate Gyrus / cytology
  • Dentate Gyrus / drug effects
  • Female
  • Hippocampus / cytology
  • Hippocampus / drug effects
  • Male
  • Neurons / drug effects*
  • Neurons / physiology
  • Pregnancy
  • Prenatal Exposure Delayed Effects* / chemically induced
  • Prenatal Exposure Delayed Effects* / physiopathology
  • Rats
  • Rats, Wistar

Substances

  • Betamethasone