Effects of scopolamine and physostigmine on acquisition of morphine-treated rats in Morris water maze performance

Acta Pharmacol Sin. 2002 May;23(5):477-80.

Abstract

Aim: To investigate effects of morphine on acquisition process of rats a nd interactions of opioid and cholinergic systems by Morris water maze performance.

Methods: Morris water maze was used to measure the latency of rats with drug s treatment to find the covert platform.

Results: Chronic morphine administration (10 mg/kg) impaired the acquisition process of rats in Morris water maze task. Appreciable difference was identified with morphine 10 mg/k g group compared with morphine 3 mg/kg group. Co-administration of morphine (10 mg/kg) and scopolamine (3 mg/kg) aggravated acquisition impairment induced by morphine 1 0 mg/kg or scopolamine alone, though scopolamine itself induced no salient changes in acquisition capabilities of rats. In addition, physostigmine (0.1 mg/kg) could appreciably attenuate morphine-induced acquisition impairment.

Conclusion: Morphine 10 mg/kg evidently impaired acquisition process of rats. There was a close relationship between the acquisition capabilities of morphine-treated rats and the functions of cholinergic system.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cholinergic Agents / pharmacology
  • Dose-Response Relationship, Drug
  • Drug Interactions
  • Male
  • Maze Learning / drug effects*
  • Morphine / pharmacology*
  • Narcotics / pharmacology
  • Physostigmine / pharmacology*
  • Rats
  • Rats, Wistar
  • Scopolamine / pharmacology*

Substances

  • Cholinergic Agents
  • Narcotics
  • Morphine
  • Physostigmine
  • Scopolamine