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Neurodevelopmental Reflex Testing in Neonatal Rat Pups
Published on: April 24, 2017
Neonatal anoxia impairs long-term energy metabolism and somatic development of Wistar rats
Natalia Andrea Cruz-Ochoa1, Julieta Esperanza Ochoa-Amaya2, Sandy Lorena Pulecio2
1Laboratório de Neurociências, Departamento de Anatomia, Instituto de Ciências Biomédicas, Universidade de São Paulo, Av. Prof. Lineu Prestes, 2415, 05508-900, São Paulo, SP, Brazil.
Insights
Neonatal anoxia reduced body weight gain and impaired long-term energy metabolism in Wistar rats, with effects varying by sex and age.
Area of Science:
- Neuroscience
- Developmental Biology
- Metabolic Research
Background:
- Neonatal anoxia can lead to neurological damage, altered behavior, and impaired somatic growth.
- Long-term effects of oxygen deprivation on energy metabolism and feeding behavior are not well understood.
- This study examines the lasting impacts of neonatal anoxia on Wistar rats' energy metabolism and development.
Purpose of the Study:
- To investigate the long-term consequences of neonatal anoxia on energy metabolism.
- To assess the effects of neonatal anoxia on somatic development into adulthood.
- To determine if these effects differ between male and female Wistar rats.
Main Methods:
- Male and female Wistar rats were exposed to 25-minute anoxia or control conditions on postnatal day 2.
- Subjects were assessed at postnatal days 35 and 95, including fasting/refeeding protocols.
- Measurements included body weight, food intake, glycemia, insulin, leptin, and Fos immunoreactivity.
Main Results:
- Neonatal anoxia reduced body weight gain in both sexes but did not affect food intake.
- At postnatal day 35, anoxia decreased post-prandial glycemia and increased insulin.
- At postnatal day 95, anoxia altered pancreatic structure, increased weight loss after fasting, and reduced leptin, insulin, and glucose levels.
Conclusions:
- Neonatal anoxia has lasting detrimental effects on energy metabolism and somatic development.
- These effects are influenced by the age and sex of the Wistar rats.
- The study highlights the critical impact of early-life oxygen deprivation on long-term physiological outcomes.
Background:
Neonatal anoxia may cause neurological injuries, behavioral alterations and changes in somatic growth. Somatic developmental changes suggest a possible effect of anoxia on energy metabolism and/or feeding behavior. Short-term effects of oxygen deficit on energy homeostasis have been described. In contrast, just a few studies report long-term effects. This study investigated the effects of neonatal anoxia on energy metabolism and somatic development at adulthood of males and females Wistar rats.
Method:
Male (m) and female (f) rats were exposed, on postnatal day 2 (P2), to either 25-min of Anoxia or Control treatment. At P34 part of the subjects of each group was fasted for 18 h, refeed for 1 h and then perfused 30 min later, at P35; the remaining subjects were submitted to these treatments at P94 and perfused at P95. Therefore, there were 8 groups: AmP35, AmP95, AfP35, AfP95, CmP35, CmP95, CfP35 and CfP95. For subjects perfused at P95, body weight and food intake were recorded up to P90. For subjects perfused at P35 and P95, glycemia, leptin and insulin were assessed after fasting and refeed. After perfusion the encephalon and pancreas were collected for Fos immunohistochemistry and Hematoxylin-Eosin stain analyses.
Results:
Even though neonatal anoxia did not interfere with regular food intake, it reduced body weight gain along growing in both male and female subjects as compared to the corresponding controls. At P35 neonatal anoxia decreased post-prandial glycemia and increased insulin. While at P95 neonatal anoxia altered the pancreatic histomorphology and increased post-fasting weight loss, decreasing leptin, insulin and glycemia secretion, as well Fos immunoreactivity (IR) in ARC.
Conclusion:
Neonatal anoxia impairs long-term energy metabolism and somatic development in Wistar rats, with differences related to sex and age.
