| The specific aim of this research was to examine the contribution that maternal exposure to methadone-induced hypoxia/hypercapnia had on adult offspring neurobehavioral development. Initial experiments confirmed that monitoring of tissue gases (tcPO;Initial, once/day injections of methadone (5 mg/kg) into pregnant rats (MC), from gestation day (GD) 4-12, caused significant hypoxia/hypercapnia. MC dams, however, showed tolerance to methadone-induced hypoxia/hypercapnia seven days later. MC neonates displayed no mortality, but morbidity (reduced body weights and delayed eye-opening) at approximately postnatal day 12-14. Adult MC offspring (both sexes) exhibited a retardation in the acquisition of autoshaped behavior and MC males pressed a lever more times on a progressive fixed ratio schedule (PFR)(FR1-32). Offspring's brains were removed, weighed, and their hippocampi analyzed for total (;Unlike offspring of MC dams, offspring of dams exposed either early (GD 4-10) or late (GD 11-17) to an AA (averaged 10.8% O... |
