Related Experiment Video
Updated: Jan 4, 2026
Manipulation of Rhythmic Food Intake in Mice Using a Custom-Made Feeding System
Published on: December 16, 2022
Early weaning disrupts feeding patterns in female juvenile rats through 5HT-system modulations
Gabriel Araújo Tavares1, Larissa Cavalcanti do Amaral Almeida2, Julliet Araújo de Souza2
1Graduate Program of Nutrition, Federal University of Pernambuco, Av. Prof. Moraes Rego, 1235, Cidade Universitária, Recife, PE, Brazil; Universidade Federal de Pernambuco - UFPE, Av. Prof. Moraes Rego, 1235, Cidade Universitária, Recife, PE, Brazil.
Insights
Early weaning in female rats alters feeding patterns and increases body weight. This behavioral change is linked to modifications in the serotonin (5-HT) system within the hypothalamus and brainstem.
Area of Science:
- Neuroscience
- Developmental Biology
- Behavioral Science
Background:
- Early disruption of maternal care and breastfeeding via weaning protocols impacts neurobehavioral development in rodents.
- The serotoninergic system plays a crucial role in regulating feeding patterns.
Purpose of the Study:
- To investigate the effects of early weaning on feeding patterns, serotonin system gene expression, and body weight in female juvenile Wistar rats.
- To assess the impact of early (postnatal day 15) versus regular (postnatal day 30) weaning on these parameters.
Main Methods:
- Comparative analysis of feeding patterns over a 24-hour period in early-weaned versus regularly weaned rats.
- Quantitative measurement of mRNA expression for serotonin 1B receptor (5-HT1B), serotonin 2C receptor (5-HT2C), and serotonin transporter (SERT) in the hypothalamus and brainstem.
- Monitoring of body weight changes in juvenile female rats subjected to different weaning protocols.
Main Results:
- Early weaning led to increased food intake, particularly during the dark phase and at the onset of dark/light phases.
- Hypothalamic expression of 5-HT1B, 5-HT2C, and SERT mRNA was decreased by early weaning, while brainstem expression was increased.
- Early-weaned rats exhibited significantly higher body weight compared to controls.
Conclusions:
- Early weaning significantly alters feeding behaviors and increases body weight in juvenile female rats.
- These behavioral modifications are associated with altered gene expression within the central serotoninergic system (5-HT).
- The findings suggest early life stress from weaning impacts neurodevelopment and metabolic regulation via the 5-HT system.
Abstract:
Convergent evidence in literature shows that rapid disruption of maternal care and breastfeeding due to an early weaning protocol changes the development of several neurobehavioral patterns in rodents, including the circadian pattern of feeding. The serotoninergic system has been associated with the control of feeding patterns. Therefore, we aim to evaluate the patterns of feeding, the mRNA expression of 5 H T-1b, 5 H T-2c, and SERT on the hypothalamus, brainstem, and the body weight of female juvenile Wistar rats, submitted to early (PND15) or regular (PND30) weaning. The results demonstrate that early weaning promotes an increase in food intake in a 24 -h period, in the dark phase of the circadian cycle and in the four-hour time intervals at the beginning of the dark and light phases. Also, early weaning decreases the mRNA expression of 5 H T-1b, 5 H T-2c, and SERT on the hypothalamus, but increases it on the brainstem. Additionally, early weaning promotes an increase in body weight. Therefore, the present data demonstrate that early weaning changes the patterns of feeding in juvenile female rats and suggests that this behavioral modification is due to the modulations promoted in the 5 H T-system.
