Microinjection of NMDA Receptor Agents into the Central Nucleus of the Amygdale Alters Water Intake in Rats

Document Type : Original Article

Authors

1 Department of Biology, Faculty of Science, Karaj Islamic Azad University, Karaj, Iran

2 Department of Veterinary Medicine, Karaj Islamic Azad University, Karaj, Iran

Abstract

Objective(s)
The central nucleus of the amygdala (CeA) is a forebrain structure which is important in regulation of ingestive behavior and there is direct and circumstantial evidence to indicate that some circuits involved with feeding behavior include glutamatergic elements. The present study examined whether administration of NMA (N-Methyl-DL-aspartic acid) or MK801 into the CeA altered water intake under deprivation.
Materials and Methods
Animals were deprived for 24 hr before tested for water intake. NMDA (N-methyl-D-aspartate) glutamatergic receptor agonist, NMA and its antagonist, MK801 were infused bilaterally, and water intake measured for 1 hr thereafter.
Results
The intra-CeA injection of NMDA glutamatergic agonist, NMA (0.25, 0.5 and 0.75 pg/rat) increased water intake (P<0.05). However, administration of NMDA glutamatergic antagonist, MK801 (0.25, 0.5 and 1 pg/rat) decreased water intake significantly (P<0.05).
Conclusion
These data suggest that NMDA receptors in the CeA are responsible for the glutamatergic modulation of water intake in this nucleus.

Keywords

References

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Iranian Journal of Basic Medical Sciences
Volume 13, Issue 1 - Serial Number 1
January 2010
Pages 238-241

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