Developmental lead exposure alters rodent maternal pup retrieval disrupting adolescent social play

Abstract

Developmental lead (Pb) exposure remains a valuable neurotoxicant rodent model of human environmentally induced cognitive disability, yet less is known about Pb-exposure on maternal pup care and its relationship to adolescent social-emotional behaviors such as social-play. Here we examined two developmental time-periods of Pb-exposure (i.e., Perinatal [PERI; pairing to day 22] and Postnatal [EPN; From Birth to day 22]), as well as the dose-response effects of Pb (i.e., 25 ppm, 150 ppm, and 1,000 ppm) administered through the drinking water. Maternal pup retrieval behaviors (i.e., latency across postnatal day (PND) 2-7) were correlated with adolescent social- play behaviors (i.e., attacks, pins, defenses, counters, and climbs) and compared against age- matched Control rats. The results showed that PERI and EPN maternal Pb-exposure increased pup * retrieval latencies from PND 5-7 when compared to Control rats. Additionally as a function of Pb- i dose, PERI maternal pup retrieval latencies increased from PNDs 5-7 with little within Pb dose- l effects. Adolescent social-play behaviors showed a sex-based increased difference in female rats engaging in more attacks, defenses, pins, counters, and climbs than males. PERI 150 ppm treated adolescent rats showed reduced female social-play behaviors, but were elevated in males. At PERI 1,000 ppm exposures, female social-play behaviors were similar to PBRI 150 ppm female rats, but interestingly males exhibited a 2- to 3-fold increase in social-play behaviors. These data suggest that environmental Pb-exposure may negatively influence maternal social care behaviors, thereby altering the natural trajectory of developmental social-emotional behaviors that emerge in adolescence with lifespan impacts. (SUNY-OW Faculty Development Grant).