Learning deficits induced by 4 belladonna alkaloids are preferentially attenuated by tacrine.

Abstract

AIM:

To examine the antagonism of tacrine on the amnesic effects of scopolamine (Sco), anisodine (AT3), atropine (Atr), and anisodamine (Ani).

METHODS:

Cognitive functions and locomotor activities were determined using two sessions of step-through and open-field tests, respectively. Mice were injected with one of the belladonna alkaloids (0.05-50 mumol.kg-1, i.p.) and tacrine (50 mumol.kg-1, s.c.) 30 min before the first session.

RESULTS:

Tacrine completely blocked the avoidance-learning deficit caused by Sco 0.5 mumol.kg-1, AT3 and Atr 5 mumol.kg-1, or Ani 50 mumol.kg-1. But tacrine partly antagonized the learning deficit induced by Sco 5-50 mumol.kg-1 or Atr and AT3 50 mumol.kg-1. The avoidance-memory deficit caused by Sco 0.05-5 mumol.kg-1 or Atr 5 mumol.kg-1 was completely or partly attenuated by tacrine, which did not antagonize the memory deficit elicited by Sco and Atr 50 mumol.kg-1, AT3 5 and 50 mumol.kg-1, and Ani 50 mumol.kg-1. During the acquisition, the locomotor activity of the mice was inhibited by tacrine. This reduction was completely antagonized by Sco 0.5-50 mumol.kg-1, AT3 5-50 mumol.kg-1, Atr 5-50 mumol.kg-1, and only partly antagonized by AT3 and Atr 0.5 mumol.kg-1 or Ani 50 mumol.kg-1.

CONCLUSION:

Compared with the avoidance-memory deficit, the avoidance-learning deficit caused by belladonna alkaloids is more preferentially attenuated by tacrine.

• Authors: S Y Pan, Y F Han
• Journal: Acta pharmacologica Sinica (Acta Pharmacol Sin) Vol. 21 Issue 2 Pg. 124-30 (Feb 2000) ISSN: 1671-4083 [Print] United States
• PMID: 11263258 (Publication Type: Journal Article)

Chemical References

• Cholinesterase Inhibitors
• Muscarinic Antagonists
• Scopolamine Derivatives
• Solanaceous Alkaloids
• anisodamine
• Tacrine
• Atropine
• Scopolamine
• anisodine

Topics

• Animals
• Atropine (antagonists & inhibitors)
• Avoidance Learning (drug effects)
• Cholinesterase Inhibitors (pharmacology)
• Learning Disabilities (chemically induced)
• Male
• Mice
• Motor Activity (drug effects)
• Muscarinic Antagonists
• Retention, Psychology (drug effects)
• Scopolamine (antagonists & inhibitors)
• Scopolamine Derivatives (antagonists & inhibitors)
• Solanaceous Alkaloids (antagonists & inhibitors)
• Tacrine (pharmacology)