Involvement of glutamate release in substance P-induced phase delays of suprachiasmatic neuron activity rhythm in vitro.
The suprachiasmatic nucleus (SCN) has been identified as a mammalian circadian rhythm clock. Treatment with substance P (SP) at zeitgeber time 13-14 produced phase delays of circadian rhythm in spontaneous neural activity in SCN neurons in vitro. SP-induced phase delays are blocked by treatment with not only SP receptor antagonist, spantide, but N-methyl-D-aspartate receptor antagonist, MK-801. In the biochemical experiment, we demonstrated that SP-induced glutamate release from the SCN slices was observed by the high-performance liquid chromatography assay. The present results suggest that glutamate release may be involved in SP-induced phase delays.
Department of Pharmacology, Faculty of Pharmaceutical Sciences, Kyushu University, Fukuoka 812-8582, Japan.
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T
Hamada
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Yamanouchi
A
A
Watanabe
S
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Shibata
S
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Watanabe
D000818:Animals; D002940:Circadian Rhythm / Q000187:drug effects*; D018698:Glutamic Acid / Q000378:metabolism*; D066298:In Vitro Techniques; D064729:Neurokinin-1 Receptor Antagonists; D051381:Rats; D011930:Reaction Time / Q000187:drug effects*; D013373:Substance P / Q000031:analogs & derivatives / Q000494:pharmacology*; D013493:Suprachiasmatic Nucleus / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism
D064729:Neurokinin-1 Receptor Antagonists; D013373:Substance P; D018698:Glutamic Acid; C042867:spantide