Related Experiment Video
Updated: Oct 17, 2026

Use of the Operant Orofacial Pain Assessment Device (OPAD) to Measure Changes in Nociceptive Behavior
Published on: June 10, 2013
Saccharin effects on morphine-induced temperature change in rats
R L Bowers1, L D Nicastle, D C Falb
1Department of Psychology, University of Charleston, SC 29424.
Abstract:
The effects of saccharin on morphine-induced temperature change was examined in Long-Evans rats. Rats were given free access to 0.15% saccharin for 15 days, followed by saccharin deprivation for 9 days. Saccharin was then returned to one group, while a second group received water. All rats were then injected with morphine sulfate (2 mg/kg), and postinjection temperatures were assessed over 75 min. The results showed that saccharin enhanced the biphasic effects of morphine by significantly increasing the hypothermic phase. The findings support the view that sweet substances influence endogenous opioid release.
Related Concept Videos
Analgesia and Pain Management
Opioid Analgesics: Synthetic and Semisynthetic Opioids

