Assessment of laparotomy-induced stress response in opium- and morphine-addicted rats by measuring serum glucose and corticosterone levels: an animal experiment.

Chronic opioid use may dampen the neuroendocrine response to surgical stress. In a rat model, animals addicted to morphine or opium showed lower corticosterone levels after laparotomy than controls, though the difference was not statistically significant. Blood glucose, a marker of stress-induced hyperglycemia, was significantly higher in control rats both immediately after surgery and 30 minutes later, indicating a sustained response that was blunted in addicted rats. No significant differences emerged between morphine- and opium-addicted groups. The findings suggest that long-term opioid exposure can alter the body's hormonal stress response, potentially affecting recovery from surgery. However, the small sample size and lack of baseline measurements limit the conclusions.

Study at a glance

Abstract

Surgical procedures induce stress responses similar to severe illnesses, activating the metabolic and neuroendocrine systems, especially the hypothalamic-pituitary-adrenal (HPA) axis. The resulting cortisol surge maintains homeostasis but can adversely affect recovery by elevating blood glucose levels and increasing the risk of complications. Given the high prevalence of opium use, especially in the Middle East and southwestern Asia, and its suspected impact on HPA axis function, this study assesses corticosterone (CS) and glucose as indicators of impaired neuroendocrine responses to surgical stress in an animal model with chronic opioid use. Thirty-six male Wistar rats were randomly assigned to three groups: morphine-addicted, opium-addicted, and control. Addiction was induced by administering increasing doses of morphine or opium in drinking water, as verified by naloxone injections. Laparotomy was performed under ketamine and xylazine anesthesia. Blood samples were collected post-surgery and post-recovery to measure the CS and glucose levels. This study included 30 rats, with 10 rats per group. Post-surgery, mean CS levels were higher in the control group compared to the addicted groups, although not significantly higher. Thirty minutes post-recovery, CS levels remained elevated in the addicted groups. Mean glucose levels were significantly higher in the control group both immediately and 30 minutes post-recovery, indicating a sustained hyperglycemic response. No significant differences were observed between addicted groups in glucose levels. Our study suggests that chronic opioid use may reduce the neuroendocrine response to surgical stress, as shown by lower CS levels in the addicted rats. This aligns with existing research on opioids and stress responses. However, the small sample size and lack of baseline measurements limit the findings. Future studies should use larger, more diverse samples and additional biomarkers. This pilot study highlights the need for further research on altered stress responses in opioid-addicted patients undergoing surgery, emphasizing the importance of tailored postoperative care.