Involvement of delta-opioid receptors in physical dependence on butorphanol.

Abstract

Butorphanol, a synthetic agonist/antagonist, has been shown to act on mu-, delta- and kappa-opioid receptors. However, the relative involvement of opioid receptor subtypes in mediating butorphanol dependence is not known. In the present study, naltrindole, a delta-selective non-peptide antagonist, was administered intracerebroventricularly (i.c.v.) to mask supraspinal delta-opioid receptors before and during the induction of butorphanol dependence. Treatment with naltrindole (0.1, 1, or 10 nmol/5 microliters per rat) significantly blocked naloxone-, a nonspecific antagonist, precipitated butorphanol withdrawal behaviors (escape behavior, teeth-chattering, wet shakes, forepaw tremors, ptosis, diarrhea, body weight loss, and hypothermia) at all doses tested, and decreased ejaculation at 0.1 nmol in butorphanol-infused rats. In contrast, naltrindole treatment had no effect on yawning, nor urination. These results indicate that central delta-opioid receptors are involved in mediating butorphanol dependence in rats.

• Authors: S P Jaw, B Hoskins, I K Ho
• Journal: European journal of pharmacology (Eur J Pharmacol) Vol. 240 Issue 1 Pg. 67-72 (Aug 10 1993) ISSN: 0014-2999 [Print] Netherlands
• PMID: 8405123 (Publication Type: Journal Article, Research Support, U.S. Gov't, P.H.S.)

Chemical References

• Enkephalins
• Receptors, Opioid, delta
• Naltrexone
• Enkephalin, D-Penicillamine (2,5)-
• naltrindole
• Butorphanol

Topics

• Animals
• Butorphanol
• Enkephalin, D-Penicillamine (2,5)-
• Enkephalins (pharmacology)
• Male
• Naltrexone (analogs & derivatives, pharmacology)
• Rats
• Rats, Sprague-Dawley
• Receptors, Opioid, delta (physiology)
• Substance-Related Disorders (etiology)