Day/night variation of 5-hydroxyindole acetic acid concentration in rat cerebrospinal fluid after acute and long-term administration of a selective serotonin reuptake inhibitor, fluvoxamine.
When 30 mg/kg, p.o. of fluvoxamine, a selective serotonin reuptake inhibitor, was administered, significant increases of 3-methoxy-4-hydroxyphenylglycol (MHPG) and 5-hydroxy indole-3-acetic acid (5-HIAA) contents in rat cerebrospinal fluid (CSF) were observed from two days after administration of fluvoxamine in both the light and dark periods and in the dark period of the light/dark cycle, respectively. In long-term treatment with 15 mg/kg, p.o. of fluvoxamine, the level of MHPG in CSF exhibited no difference, whereas the levels of 5-HIAA showed a significant increase during the light periods. These results suggest that fluvoxamine enhances the 5-HT system, but only with long-term treatment.
Egashira
T
T
Department of Pharmacology, Oita Medical University, Japan.
Takayama
F
F
Yamanaka
Y
Y
Takada
K
K
Takeda
H
H
Matsumiya
T
T
D000818:Animals; D002940:Circadian Rhythm / Q000187:drug effects* / Q000502:physiology; D016666:Fluvoxamine / Q000008:administration & dosage*; D006897:Hydroxyindoleacetic Acid / Q000134:cerebrospinal fluid*; D008297:Male; D008734:Methoxyhydroxyphenylglycol / Q000134:cerebrospinal fluid*; D051381:Rats; D017208:Rats, Wistar; D017367:Selective Serotonin Reuptake Inhibitors / Q000008:administration & dosage*
D016666:Fluvoxamine; D006897:Hydroxyindoleacetic Acid; D008734:Methoxyhydroxyphenylglycol; D017367:Selective Serotonin Reuptake Inhibitors