Effect of chronic Albizzia julibrissin treatment on 5-hydroxytryptamine1A receptors in rat brain.
Quantitative receptor autoradiography and behavioral studies were employed to investigate whether the aqueous extract of Albizzia julibrissin (AEAJ) specifically targets serotonergic systems in rat brain. AEAJ was orally administered at 50 and 200 mg/kg to adult male SD rats for 7 days. Treatment with AEAJ (200 mg/kg) significantly increased time-spent in open arms and the number of open arm entries in an elevated plus-maze (EPM) versus saline controls (P<0.05). Moreover, those effects of AEAJ were blocked by WAY 100635, a 5-HT1A receptor antagonist. Following behavioral evaluation, the binding of [3H]8-hyroxy-2-(di-n-propylamino) tertalin ([3H]8-OH-DPAT) to 5-HT1A receptors in rat brain was investigated. [3H]8-OH-DPAT binding after AEAJ (200 mg/kg) treatment showed a marked increase in the frontal cortex, hippocampus (CA2 and CA3 regions) and in the lateral septum versus vehicle-treated controls. No changes of [3H]8-OH-DPAT binding were observed in the caudate putamen, dentate gyrus and CA1 areas of the hippocampus or in the hypothalamus. In the dorsal raphe region, [3H]8-OH-DPAT binding was significantly reduced by AEAJ (50 mg/kg) treatment but was unchanged by AEAJ (200 mg/kg). These results suggest that the anxiolytic-like effect of A. julibrissin is mediated by the changes of serotonergic nervous system, especially 5-HT1A receptors.
Jung
Ji Wook
JW
Department of Oriental Pharmaceutical Science, College of Pharmacy, Kyung Hee University, 1 Hoeki-dong, Dongdeamoon-ku, Seoul 130-701, Korea.
Cho
Jae-Han
JH
Ahn
Nam Yoon
NY
Oh
Hye Rim
HR
Kim
Sun Yeou
SY
Jang
Choon-Gon
CG
Ryu
Jong Hoon
JH
D031289:Albizzia; D000818:Animals; D001921:Brain / Q000187:drug effects* / Q000378:metabolism*; D004305:Dose-Response Relationship, Drug; D008297:Male; D018782:Maze Learning / Q000187:drug effects / Q000502:physiology; D024301:Plant Bark; D010936:Plant Extracts / Q000302:isolation & purification / Q000494:pharmacology; D011485:Protein Binding / Q000187:drug effects / Q000502:physiology; D051381:Rats; D017207:Rats, Sprague-Dawley; D044282:Receptor, Serotonin, 5-HT1A / Q000378:metabolism*; D058825:Serotonin 5-HT1 Receptor Agonists; D058829:Serotonin 5-HT1 Receptor Antagonists
D010936:Plant Extracts; D058825:Serotonin 5-HT1 Receptor Agonists; D058829:Serotonin 5-HT1 Receptor Antagonists; D044282:Receptor, Serotonin, 5-HT1A