Effects of intracerebroventricular injection of alpha-fluoromethylhistidine on radial maze performance in rats.

Abstract

The effects of alpha-fluoromethylhistidine (alpha-FMH) on spatial cognition were investigated using the eight-arm radial maze paradigm in rats. Intracerebroventricular (ICV) injection of alpha-FMH resulted in spatial memory deficits characterized by an increase in the number of total errors (TE) and a decrease in the number of initial correct responses (ICR). There was a strong correlation between increases in the number of TE and decreases in histamine contents of the cortex and hippocampus regions of the brain, which are known to participate in learning and memory. On the other hand, both histamine (50-100 ng, ICV) and thioperamide (10 microg, ICV) significantly ameliorated the memory deficit induced by alpha-FMH. However, metoprine showed no significant effect on the alpha-FMH-induced memory deficit. Pyrilamine and R-(alpha)-methylhistamine enhanced the memory deficit induced by alpha-FMH, at doses that had no appreciable effect when administered alone. In contrast, no significant influence on alpha-FMH-induced memory deficit was observed with zolantidine.

• Authors: Z Chen, Y Sugimoto, C Kamei
• Journal: Pharmacology, biochemistry, and behavior (Pharmacol Biochem Behav) Vol. 64 Issue 3 Pg. 513-8 (Nov 1999) ISSN: 0091-3057 [Print] United States
• PMID: 10548264 (Publication Type: Journal Article)

Chemical References

• Enzyme Inhibitors
• Histamine H1 Antagonists
• Histamine H2 Antagonists
• Methylhistidines
• alpha-fluoromethylhistidine
• Histamine
• Histidine Decarboxylase

Topics

• Animals
• Brain Chemistry (drug effects)
• Cerebral Cortex (drug effects, metabolism)
• Enzyme Inhibitors (administration & dosage, pharmacology)
• Hippocampus (drug effects, metabolism)
• Histamine (metabolism, physiology)
• Histamine H1 Antagonists (pharmacology)
• Histamine H2 Antagonists (pharmacology)
• Histidine Decarboxylase (antagonists & inhibitors)
• Hypothalamus (drug effects, metabolism)
• Injections, Intraventricular
• Male
• Maze Learning (drug effects)
• Memory (drug effects)
• Methylhistidines (administration & dosage, pharmacology)
• Psychomotor Performance (drug effects)
• Rats
• Rats, Wistar