Effects of adolescent nicotine exposure on opioid consumption and neuroendocrine responses in adult male and female rats.

Effects of adolescent nicotine exposure on illicit drug consumption and neuroendocrine functioning were examined in adult rats. Nicotine (NIC; 2 doses) or saline (SAL) was administered via osmotic minipumps to 30 male and 30 female adolescent Wistar rats for 19 days. After NIC/SAL cessation, oral opioid consumption was assessed in the home cage for 4 weeks. Plasma corticosterone and ACTH were measured at the end of the experiment. Low-NIC male rats consumed more fentanyl than did high-NIC male rats; opioid consumption among adult female rats was not altered by NIC exposure. Females consumed more fentanyl than did males, regardless of NIC history. NIC exposure increased adult corticosterone and ACTH levels in a dose-dependent manner. Results suggest important effects of adolescent NIC exposure, including altered neuroendocrine status and opioid consumption.