Locomotor activity and contracture of isolated ileum precipitated by naloxone following treatment of guinea-pigs with a single dose of morphine.

Abstract

Guinea-pigs treated with a single dose of morphine, 15 mg kg-1 s.c., exhibited an increase in locomotor activity 2 h later on injection of naloxone, 4 mg kg-1 i.p. At the same time, contracture of ileal preparations isolated from morphine-treated guinea-pigs occurred on addition of naloxone 1 microM. Contracture of the ileum was inhibited by the tachykinin antagonist, spantide, and was therefore presumably mediated by a substance P-like agent. This study has established a useful model for the parallel investigation of central and enteric nervous system mechanisms of opiate dependence.

• Authors: L A Chahl, C A Thornton
• Journal: The Journal of pharmacy and pharmacology (J Pharm Pharmacol) Vol. 39 Issue 1 Pg. 52-4 (Jan 1987) ISSN: 0022-3573 [Print] England
• PMID: 2434641 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Substance P
• Naloxone
• Morphine
• Atropine
• spantide

Topics

• Animals
• Atropine (pharmacology)
• Female
• Gastrointestinal Motility (drug effects)
• Guinea Pigs
• Ileum (drug effects)
• In Vitro Techniques
• Male
• Morphine (pharmacology)
• Motor Activity (drug effects)
• Naloxone (pharmacology)
• Substance P (analogs & derivatives, antagonists & inhibitors, pharmacology)
• Substance Withdrawal Syndrome (chemically induced)