Disrupted Maternal Behavior in Morphine-Dependent Pregnant Rats and Anhedonia in their Offspring

Area of Science:

• Neuroscience
• Developmental Psychology
• Pharmacology

Background:

• Opioid use disorder affects infants, causing withdrawal and early life trauma.
• Gestational opioid exposure is linked to long-term social, conduct, and emotional disorders in children.

Purpose of the Study:

• Investigate the impact of perinatal opioid exposure (POE) on anhedonia and stress-related behaviors in male and female Sprague Dawley rats.
• Examine the effects of maternal morphine administration on maternal behavior and offspring neurodevelopment.

Main Methods:

• Administered morphine to pregnant rats via subcutaneous micro-infusion pumps before, during, and post-gestation.
• Assessed maternal behavior (fragmentation, entropy) and offspring behaviors (sucrose preference, social interaction, stress responsivity).
• Measured corticosterone levels and analyzed brain region activity in offspring.

Main Results:

• Maternal morphine exposure resulted in fragmented nursing behavior and higher entropy.
• Offspring displayed reduced sucrose preference and social interaction, with altered mesolimbic reward pathway activity.
• Adult male offspring exposed to morphine showed increased corticosterone levels.

Conclusions:

• Perinatal morphine exposure induces anhedonic behaviors and social deficits in rat offspring.
• Disrupted maternal care in opioid-dependent dams may contribute to these long-term behavioral changes.
• Findings highlight the critical impact of prenatal opioid exposure on neurodevelopment and behavior.