1Neuroscience
Research Laboratory, Dr. Panjwani Center for Molecular Medicine and
Drug Research, International Center for Chemical and Biological
Sciences, University of Karachi, Karachi-75270, Pakistan;
2Department
of Physiology, Wah Medical College, Wah Cantt-47040, Pakistan
*Corresponding author:
shazianawaz19@gmail.com
Abstract
Nalbuphine, a semi-synthetic opioid drug, is a
kappa (κ) agonist/ mu (μ) partial agonist.It is clinically used for moderate to severe pain. It produces the
analgesic effect largely by binding to kappa opioid receptors. The present study
was designed to investigate locomotor sensitization as well reinforcing effects
of different doses (5, 10 and 20 mg/kg) of nalbuphine in rats. Potential
analgesic and hyperalgesic effects after single and repeated administration
respectively were also monitored. Reinforcing effects were monitored in a
conditioned place preference (CPP) paradigm and associated changes in motor
activity were monitored during a drug conditioning phase. The hot plate test was
used to monitor nociceptive response. The present study showed that low (5
mg/kg) and high (20 mg/kg) doses of nalbuphine were reinforcing, while the
moderate dose (10 mg/kg) had no reinforcing effect in the CPP paradigm. All
doses were analgesic after the first administration and on repeated
administration hyperalgesia did not develop to any dose. Analgesic effects still
occurred at moderate doses of nalbuphine. Sensitization-like effects were
produced following moderate and high doses of nalbuphine. These findings
suggested that a moderate dose of nalbuphine did not produce reinforcing effects
and hyperalgesia so this dose can be used safely for treating pain.
To Cite This Article:
Nawaz S, Salman T, Gul S and Haleem DJ, 2021.
Dose related analgesic, motor and
reinforcing effects of nalbuphine in rats. Pak Vet J, 41(4): 487-492.
http://dx.doi.org/10.29261/pakvetj/2021.066