Tags

Type your tag names separated by a space and hit enter

Differential effects of exogenous and endogenous estrogen on anxiety as measured by elevated T-maze in relation to the serotonergic system.
Behav Brain Res. 2009 Mar 02; 198(1):142-8.BB

Abstract

The effects of estrogen on anxiety-like behaviors have been widely studied but the mechanisms responsible are still inconclusive. The purpose of the current study was to compare the effects of transient high levels of endogenous estrogen and chronic exogenous estrogen treatment on the anxiety-like behaviors using the elevated T-maze (ETM) test. In addition, serotonin (5-HT) and its metabolite (5-HIAA), serotonin reuptake transporter (SERT) and tryptophan hydroxylase enzyme (TPH) were measured at the end of the study and correlated to the task performances. Female sham-operated rats in proestrous phase (Sham-Pro) and ovariectomized rats treated with or without 17beta-estradiol (10 microg/kg, s.c.; Ovx+E(2) or Ovx) for 4 weeks were used. In the ETM test, the Ovx+E(2) group had reduced inhibitory avoidance responses compared to others, suggesting that exogenous E(2) replacement is anxiolytic, while escape latency was prolonged in the Sham-Pro group suggesting endogenous E(2) is panicolytic. Further, the serotonin turnover rate (5-HIAA/5-HT ratio) in the hippocampus and nucleus accumbens was highest in the Ovx+E(2) group. While the TPH protein in the midbrain of Ovx rats was significantly higher than others, the SERT levels were not significantly different among groups in all measured brain areas. In conclusion, Ovx rats with chronic estrogen administration and Sham-Pro rats with naturally high levels of estrogen, demonstrated anxiolytic behavior by exhibiting different forms of anxiety that related to the changes in the function of serotonergic system.

Links

Publisher Full Text
Aggregator Full Text

Authors+Show Affiliations

Pandaranandaka J
Physiology Division, Preclinical Sciences, Faculty of Medicine, Thammasat University, Prathumtani, Thailand.
Poonyachoti S
No affiliation info available
Kalandakanond-Thongsong S
No affiliation info available

MeSH

Analysis of VarianceAnimalsAnxietyAvoidance LearningBrainChromatography, High Pressure LiquidEstradiolEstrogensExploratory BehaviorFemaleHippocampusHydroxyindoleacetic AcidInjections, SubcutaneousMaze LearningMesencephalonMotor ActivityNucleus AccumbensOvariectomyRatsRats, WistarSerotoninSerotonin Plasma Membrane Transport ProteinsTime FactorsTryptophan Hydroxylase

Pub Type(s)

Journal Article
Research Support, Non-U.S. Gov't

Language

eng

PubMed ID

19046994

Citation

Pandaranandaka, Jantarima, et al. "Differential Effects of Exogenous and Endogenous Estrogen On Anxiety as Measured By Elevated T-maze in Relation to the Serotonergic System." Behavioural Brain Research, vol. 198, no. 1, 2009, pp. 142-8.
Pandaranandaka J, Poonyachoti S, Kalandakanond-Thongsong S. Differential effects of exogenous and endogenous estrogen on anxiety as measured by elevated T-maze in relation to the serotonergic system. Behav Brain Res. 2009;198(1):142-8.
Pandaranandaka, J., Poonyachoti, S., & Kalandakanond-Thongsong, S. (2009). Differential effects of exogenous and endogenous estrogen on anxiety as measured by elevated T-maze in relation to the serotonergic system. Behavioural Brain Research, 198(1), 142-8. https://doi.org/10.1016/j.bbr.2008.10.043
Pandaranandaka J, Poonyachoti S, Kalandakanond-Thongsong S. Differential Effects of Exogenous and Endogenous Estrogen On Anxiety as Measured By Elevated T-maze in Relation to the Serotonergic System. Behav Brain Res. 2009 Mar 2;198(1):142-8. PubMed PMID: 19046994.
* Article titles in AMA citation format should be in sentence-case
TY - JOUR T1 - Differential effects of exogenous and endogenous estrogen on anxiety as measured by elevated T-maze in relation to the serotonergic system. AU - Pandaranandaka,Jantarima, AU - Poonyachoti,Sutthasinee, AU - Kalandakanond-Thongsong,Sarinee, Y1 - 2008/11/12/ PY - 2008/04/24/received PY - 2008/10/18/revised PY - 2008/10/23/accepted PY - 2008/12/3/pubmed PY - 2009/3/31/medline PY - 2008/12/3/entrez SP - 142 EP - 8 JF - Behavioural brain research JO - Behav Brain Res VL - 198 IS - 1 N2 - The effects of estrogen on anxiety-like behaviors have been widely studied but the mechanisms responsible are still inconclusive. The purpose of the current study was to compare the effects of transient high levels of endogenous estrogen and chronic exogenous estrogen treatment on the anxiety-like behaviors using the elevated T-maze (ETM) test. In addition, serotonin (5-HT) and its metabolite (5-HIAA), serotonin reuptake transporter (SERT) and tryptophan hydroxylase enzyme (TPH) were measured at the end of the study and correlated to the task performances. Female sham-operated rats in proestrous phase (Sham-Pro) and ovariectomized rats treated with or without 17beta-estradiol (10 microg/kg, s.c.; Ovx+E(2) or Ovx) for 4 weeks were used. In the ETM test, the Ovx+E(2) group had reduced inhibitory avoidance responses compared to others, suggesting that exogenous E(2) replacement is anxiolytic, while escape latency was prolonged in the Sham-Pro group suggesting endogenous E(2) is panicolytic. Further, the serotonin turnover rate (5-HIAA/5-HT ratio) in the hippocampus and nucleus accumbens was highest in the Ovx+E(2) group. While the TPH protein in the midbrain of Ovx rats was significantly higher than others, the SERT levels were not significantly different among groups in all measured brain areas. In conclusion, Ovx rats with chronic estrogen administration and Sham-Pro rats with naturally high levels of estrogen, demonstrated anxiolytic behavior by exhibiting different forms of anxiety that related to the changes in the function of serotonergic system. SN - 1872-7549 UR - https://www.unboundmedicine.com/medline/citation/19046994/Differential_effects_of_exogenous_and_endogenous_estrogen_on_anxiety_as_measured_by_elevated_T_maze_in_relation_to_the_serotonergic_system_ L2 - https://linkinghub.elsevier.com/retrieve/pii/S0166-4328(08)00619-0 DB - PRIME DP - Unbound Medicine ER -