Accepted in revised form 12 October 2001; recieved 9 August 2001.
The role of excitatory amino acids - glutamate and aspartate - in the sleep-waking cycle was investigated in the rats. Experiments were carried out in chronic preparations with stereotaxically implanted recording electrodes and cannulae. The latter was used for the lateral ventricle liquor sampling. Experiments have shown that the content of aspartate is maximal in slow-wave sleep and decreases during paradoxical sleep and, especially, during active waking. Concentration of glutamate was found to be increased during slow-wave sleep and in narcotized animals, and like aspartate in decreases in paradoxical sleep and waking. It was founded as well that arginine concentration fluctuates in a similar way. Besides the amino acids, concentration of ammonia was assessed in various phases of sleep-waking cycle. Increase of ammonia was found during paradoxical sleep and active waking.
Key Words: Waking, Paradoxical sleep, Slow-wave sleep, Aspartate, Glutamate, Arginine, NO, Ammonia, Rats.
Acknowledgments
This work was supported by the grant of the Georgian Academy of Sciences.
Correspondence: Beradze G., PhD.,
Department of Neurobiology of Sleep-Wakefulness Cycle,
I.S. Beritashvili Institute of Physiology, Georgian Academy of Sciences,
14, L. Gotua str., Tbilisi, 380060, Georgia.
E-mail: nswc@neurobiology.ge