Differential behavioral functioning in the offspring of rats with high vs. low self-administration of the opioid agonist remifentanil

• Published in: European journal of pharmacology Vol. 909; p. 174407
• Main Authors: Rezvani, Amir H., Wells, Corinne, Hawkey, Andrew, Blair, Graham, Koburov, Reese, Ko, Ashley, Schwartz, Andrea, Kim, Veronica J., Levin, Edward D.
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 15.10.2021
• Subjects: Analgesics, Opioid - administration & dosage; Analgesics, Opioid - adverse effects; Animals; Anxiety; Behavior, Animal - drug effects; Behavior, Animal - physiology; Disease Models, Animal; Dose-Response Relationship, Drug; Female; Hotplate test; Humans; Locomotor activity; Male; Maternal Exposure - adverse effects; Nociception; Opioid-Related Disorders - physiopathology; Opioids; Paternal Exposure - adverse effects; Rats; Remifentanil - administration & dosage; Remifentanil - adverse effects; Self Administration; Hotplate test; Nociception; Self-administration; Anxiety; Locomotor activity; Opioids
• ISSN: 0014-2999; 1879-0712
• DOI: 10.1016/j.ejphar.2021.174407

Opioid use disorder (OUD) has a variety of adverse effects on both the users and their offspring. In the current study, a random group of Sprague-Dawley rats (25 females and 15 males) were tested for intravenous self-administration of the opioid agonist remifentanil to determine the range of acquisition for opioid. One-month after the end of self-administration of remifentanil, rats with the highest intake were mated together and rats with lowest intake were mated together. Then, the offspring of the two groups were tested for anxiety-like behavior, locomotor activity, nociception and intravenous remifentanil self-administration. The parents showed a range of remifentanil self-administration, especially in the female rats. The offspring of the parents with low and high remifentanil self-administration showed significant differences in specific behavioral functions. On the hotplate test of nociception, the female offspring parents with high remifentanil self-administration had significantly longer hotplate latencies, indicating reduced nociception, than the female offspring of parents with low remifentanil-self-administration, whereas there was no difference in the male offspring of low and high responding parents. In the elevated plus maze test of anxiety-like behavior, the offspring of the parents with high remifentanil intake showed more anxiety-like behavior than the offspring of the parents with low remifentanil intake regardless of sex. Locomotor activity was not significantly different. Interestingly, no significant differences in remifentanil self-administration in the offspring of parents with low and high remifentanil self-administration were detected. Overall, our data suggest a considerable range in remifentanil self-administration in rats and the offspring of rats with high opioid self-administration exhibit different behaviors vs offspring of rats with low opioid self-administration.