Abstract
In order to elucidate the role of excitatory and inhibitory transmitters within the suprachiasmatic nucleus (SCN) in the circadian change of 2-deoxyglucose (2-DG) uptake in this nucleus, the effects of 8-hydroxy-2-(di-n-propylamino) tetralin hydrobromide (8-OH-DPAT), muscimol, flurazepam, pentobarbital and glutamate on uptake of 2-DG by hamster SCN were examined in hypothalamic slice preparations. 2-DG uptake in the SCN was high during the subjective day and low during the subjective night. The high uptake of 2-DG in the SCN during the daytime was inhibited by the superfusion of 8-OH-DPAT, muscimol, flurazepam and pentobarbital in a dose-dependent manner, but the low uptake of 2-DG during the night was unaffected. The low uptake during the night was significantly increased by treatment with glutamate, whereas 2-DG uptake during the day was unaffected. In contrast to the above results, 20 mM KCl and 1 μM tetrodotoxin increased and decreased 2-DG uptake during both the day and night, respectively. The present results strongly suggest that agonists of 5-HT1A receptors and GABAA-benzoadiazepine-barbiturate complex receptors regulate the function of the SCN through their inhibitory action on 2-DG uptake during the day, and that glutamate also regulates SCN function through it stimulatory action on 2-DG uptake during the night.
Original language | English |
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Pages (from-to) | 79-84 |
Number of pages | 6 |
Journal | European Journal of Pharmacology |
Volume | 217 |
Issue number | 1 |
DOIs | |
Publication status | Published - 1992 Jun 24 |
Externally published | Yes |
Keywords
- 2-Deoxyglucose uptake
- 8-OH-DPAT (8-hydroxy-2-(di-n-propylamino)tetralin)
- Benzodiazepine receptors
- Circadian rhythym
- GABA receptors
- Suprachiasmatic nucleus
ASJC Scopus subject areas
- Pharmacology