Effects of the NMDA antagonist MK-801 on radial maze performance in histidine-deficient rats.

Abstract

We examined the effects of a histidine-deficient diet on brain histamine contents as well as on learning and memory using the eight-arm radial maze in rats. A significant decrease in histamine content in the hippocampus was observed after long-term feeding of rats with a histidine-deficient diet. At the same time, significant enhancement of the acquisition process in radial maze performance was also observed. Pyrilamine did not show a significant effect on radial maze performance in histidine-deficient rats. On the other hand, pyrilamine caused a significant spatial memory deficit in control rats. Scopolamine was effective in inhibiting spatial memory in both histidine-deficient and control rats. MK-801 caused spatial memory deficits more potently in histidine-deficient rats than in controls. Brain glycine contents showed a significant increase in the hippocampus in histidine-deficient rats. These results indicated that the spatial memory deficits induced by MK-801 in histidine-deficient rats are closely related to increased glycine levels and activation of NMDA receptors.

• Authors: Miyuki Nishiga, Yukio Sugimoto, Chiyomi Taga, Yoko Fujii, Chiaki Kamei
• Journal: Life sciences (Life Sci) Vol. 70 Issue 18 Pg. 2199-208 (Mar 22 2002) ISSN: 0024-3205 [Print] Netherlands
• PMID: 12002811 (Publication Type: Journal Article)

Chemical References

• Amino Acids
• Excitatory Amino Acid Antagonists
• Histamine H1 Antagonists
• Histidine
• Dizocilpine Maleate
• Scopolamine
• Pyrilamine

Topics

• Amino Acids (metabolism)
• Animals
• Brain (drug effects, metabolism)
• Diet
• Dizocilpine Maleate (pharmacology)
• Excitatory Amino Acid Antagonists (pharmacology)
• Histamine H1 Antagonists (pharmacology)
• Histidine (deficiency)
• Male
• Maze Learning (drug effects)
• Memory Disorders (etiology, metabolism)
• Pyrilamine (pharmacology)
• Rats
• Rats, Wistar
• Scopolamine (pharmacology)