Vardenafil Increases Cell Proliferation in the Dentate Gyrus through Enhancement of Serotonin Expression in the Rat Dorsal Raphe.
10.3346/jkms.2009.24.6.1099
- Author:
Tae Soo KIM
1
;
Il Gyu KO
;
Yun Hee SUNG
;
Sung Eun KIM
;
Bo Kyun KIM
;
Seung Kook PARK
;
Mal Soon SHIN
;
Chang Ju KIM
;
Sang Jin YOON
;
Khae Hawn KIM
Author Information
1. Department of Physiology, College of Medicine, Kyung Hee University, Seoul, Korea.
- Publication Type:Original Article ; Research Support, Non-U.S. Gov't
- Keywords:
Vardenafil;
Dentate Gyrus;
Cell Proliferation;
Serotonin;
Tryptophan Hydroxylase
- MeSH:
Animals;
Cell Proliferation/*drug effects;
*Dentate Gyrus/cytology/drug effects/metabolism;
Imidazoles/*pharmacology;
Male;
Phosphodiesterase Inhibitors/*pharmacology;
Piperazines/*pharmacology;
*Raphe Nuclei/cytology/drug effects/metabolism;
Rats;
Rats, Sprague-Dawley;
Serotonin/*biosynthesis;
Sulfones/pharmacology;
Triazines/pharmacology;
Tryptophan Hydroxylase/metabolism
- From:Journal of Korean Medical Science
2009;24(6):1099-1104
- CountryRepublic of Korea
- Language:English
-
Abstract:
This study was conducted to evaluate the effects of vardenafil (Levitra), a phosphodiesterase-5 (PDE-5) inhibitor, on cell proliferation in the hippocampal dentate gyrus and on 5-hyroxytryptamine (5-HT, serotonin) synthesis and tryptophan hydroxylase (TPH) expression in the rat dorsal raphe nucleus. Male Sprague-Dawley rats were divided into 6 groups (n=5 in each group): a control group, a 0.5 mg/kg-1 day vardenafil-treated group, a 1 mg/kg-1 day vardenafil-treated group, a 2 mg/kg-1 day vardenafil-treated group, a 1 mg/kg-3 day vardenafil-treated group, and a 1 mg/kg-7 day vardenafil-treated group. 5-bromo-2'-deoxyuridine (BrdU) immunohistochemistry was then performed to evaluate cell proliferation in the dentate gyrus. In addition, 5-HT and TPH immunohistochemistry was conducted to evaluate serotonin expression in the dorsal raphe. The results revealed that treatment with vardenafil increased cell proliferation in the dentate gyrus and enhanced 5-HT synthesis and TPH expression in the dorsal raphe in a dose- and duration-dependent manner. The findings demonstrate that the increasing effect of vardenafil on cell proliferation is closely associated with the enhancing effect of vardenafil on serotonin expression under normal conditions.
