Postnatal Maternal Deprivation Induces Anxious Behaviors, Depressive Behaviors, and Increased Central Inflammation and Oxidative Stress in Adult Rats

Abstract

During the postnatal period, the organism is highly dependent on the primary caregiver for nursing and protection. The disruption of the maternal-offspring relationship has been widely assessed in animal models. A less investigated paradigm is the separation of the offspring from both their mothers and other littermates, commonly referred to as maternal deprivation (MD). In our study, we chose to investigate the effects of this deprivation on behavioural and biochemical outcomes in adult male and female Wistar rats. Rats were divided into five groups. A control group was left undisturbed, while the experimental design included four groups. Three of these groups underwent continuous 24hour maternal deprivation (MD) at varying postnatal stages (day 3, 5, or 9), and one group experienced episodic MD for 8hours daily from day 3 to day 5. Each group comprised 16 rats with an equal distribution of genders. Upon reaching 90 days of age, the rats underwent behavioral assessments alongside biochemical analyses focusing on oxidative and inflammatory markers. Generally, exposure to MD during different postnatal periods, whether continuous or episodic, resulted in reduced locomotor activity, consistent anxiogenic behaviors, a depressive response, and elevated levels of oxidative stress and inflammation. Female rats subjected to maternal deprivation exhibited greater stress sensitivity and higher inflammatory and oxidative responses compared to males. It appears that the response to MD is influenced by factors such as duration, frequency, and timing of deprivation, suggesting a complex modulation of these effects.