Related Experiment Video
Updated: Jun 5, 2026
Using Chronic Social Stress to Model Postpartum Depression in Lactating Rodents
Published on: June 10, 2013
Maternal stress affects postnatal growth and the pituitary expression of prolactin in mouse offspring
Pengfei Gao1, Atsushi Ishige, Yu Murakami
1Center for Kampo Medicine, Keio University School of Medicine, Tokyo, Japan.
Insights
Maternal stress during lactation caused low body weight in male mouse pups, persisting into adulthood. This was linked to reduced pituitary prolactin (PRL) expression and growth hormone (GH) in offspring.
Area of Science:
- Endocrinology
- Neuroscience
- Developmental Biology
Background:
- Maternal stress can negatively impact offspring health long-term.
- The specific effects of maternal stress on postnatal growth are not well-documented.
Purpose of the Study:
- To investigate the impact of maternal immobilization stress (IS) during lactation on the postnatal growth of male mouse offspring.
- To explore the underlying hormonal and molecular mechanisms in the offspring's pituitary gland.
Main Methods:
- Maternal immobilization stress (IS) was applied during lactation in mice.
- Body weight, serum insulin-like growth factor-1 (IGF-1) levels, and anterior pituitary hormone mRNA expression (GH, PRL, PIT1, PITX2, PROP1) were analyzed in offspring.
- Pituitary PRL protein expression was assessed using immunohistochemistry.
Main Results:
- Maternal IS led to significantly lower body weight in male offspring, persisting post-weaning.
- IS induced maternal malnutrition and decreased serum IGF-1 in both mothers and pups.
- Offspring exposed to IS showed reduced growth hormone (GH) and prolactin (PRL) mRNA expression, along with decreased PIT1 and PITX2 expression.
- Pituitary PRL protein levels were also reduced in IS-exposed offspring.
Conclusions:
- Postpartum maternal stress has persistent detrimental effects on offspring body weight.
- Reduced prolactin (PRL) expression in the pituitary gland of offspring appears to be a key factor contributing to these growth deficits.
Abstract:
Maternal stress exerts long-lasting psychiatric and somatic on offspring, which persist into adulthood. However, the effect of maternal stress on the postnatal growth of pups has not been widely reported. In this study, we found that maternal immobilization stress (IS) during lactation resulted in low body weight of male mouse offspring, which persisted after weaning. Despite free access to chow, IS induced maternal malnutrition and decreased the serum insulin-like growth factor-1 (IGF-1) levels in the mothers and in the pups. mRNA expression analysis of anterior pituitary hormones in the pups revealed that growth hormone (GH) and prolactin (PRL), but no other hormones, were decreased by IS. Expression of the pituitary transcription factor PIT1 and isoforms of PITX2, which are essential for the development and function of GH-producing somatotropes and PRL-producing lactotropes, was decreased, whereas that of PROP1, which is critical for the earlier stages of pituitary development, was unchanged. Immunohistochemistry also showed a decrease in pituitary PRL protein expression. These results suggest that stress in a postpartum mother has persistent effects on the body weight of the offspring. Reduced PRL expression in the offspring's pituitary gland may play a role in these effects.
