Time-dependent effect of glutamate on long-term potentiation in the suprachiasmatic nucleus of rats.
The effect of glutamate on optic nerve stimulation-evoked field potentials in rat suprachiasmatic nucleus (SCN) was examined in vitro. Glutamate application for 20 min induced long-term potentiation (LTP) of the field potentials in the SCN at nighttime, whereas that induced a weak LTP at daytime. On the other hand, application for 40 min induced LTP in the SCN during the daytime, whereas it induced a weak one at nighttime. These results indicate that the effect of glutamate is dependent on the application time and that the effect is influenced by the duration of glutamate exposure.
Nisikawa
Yukiko
Y
Department of Pharmacology, Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka, Japan.
Shimazoe
Takao
T
Shibata
Shigenobu
S
Watanabe
Shigenori
S
D000818:Animals; D002940:Circadian Rhythm; D005071:Evoked Potentials; D018698:Glutamic Acid / Q000008:administration & dosage / Q000494:pharmacology* / Q000502:physiology; D066298:In Vitro Techniques; D017774:Long-Term Potentiation / Q000187:drug effects* / Q000502:physiology; D009900:Optic Nerve / Q000187:drug effects / Q000502:physiology; D051381:Rats; D017208:Rats, Wistar; D013493:Suprachiasmatic Nucleus / Q000187:drug effects* / Q000502:physiology; D013997:Time Factors
D018698:Glutamic Acid