A new model as an early life manipulation: Fake mother

Abstract

Introduction

Early life stressful events cause long-term neural changes that are associated with psychiatric disorders.

Objective

Early life manipulations focus on commonly the impact of remaining separate from the mother in a specific period of time. The maternal odor is required for pups to approach the mother for nursing. What happens when there is a mother that smell like a real mother but does not take care her own pups?

Aim

To investigate the fake mother effects on adult rat's behavioral changes, NMDR2B protein level changes in prefrontal cortex and hippocampus.

Methods

Wistar rats were used. Fake mother (n:13), early handling (n:12), maternal separation (n:14) and control (n:12) were the study groups. A fake mother is an object that smells like a real dam. When the real mother is separated from own pups fake mother stays with the pups for an hour. Manipulations were made during the postnatal first 14 days. Behavioral tests (social interaction test, elevated plus maze, novel object recognition test) were made between postnatal 62 and 78 days. NMDAR2B protein levels in prefrontal cortex and hippocampus were evaluated by using ELISA at postnatal 78 days.

Results

In social interaction test, fake mother group exhibited less social behavior and more aggressive behavior than the other groups. Their long-term memory functions were the lowest. NMDAR2B protein levels in the hippocampus increased in rats that exposed to early stressful life events.

Conclusion

These results support that being raised by fake mother increases aggressive behavior and decrease social behavior in adulthood.

Disclosure of interest

The authors have not supplied their declaration of competing interest.