TY - JOUR
T1 - Chronic administration of tibolone modulates anxiety-like behavior and enhances cognitive performance in ovariectomized rats
AU - Espinosa-Raya, Judith
AU - Neri-Gómez, Teresa
AU - Orozco-Suárez, Sandra
AU - Campos, María G.
AU - Guerra-Araiza, Christian
N1 - Funding Information:
This study was supported by COFAA , SIP-IPN and FIS/IMSS project No. FIS/IMSS/PROT/G09/751 . Teresa Neri-Gómez received financial support from COMECYT .
PY - 2012/1
Y1 - 2012/1
N2 - Hormone replacement therapy (HRT) may be prescribed to prevent the symptoms of menopause. This therapy may include estrogenic and/or progestin components and may increase the incidence of endometrial and breast cancers. Tibolone (TIB), which is also made up of estrogen and progestin components, is often used to reduce the impact of HRT. However, the effect of TIB on the processes of learning, memory and anxiety has yet to be fully elucidated. The aim of this study was to evaluate the long-term effect on learning, memory processes and anxiety in ovariectomized rats caused by different doses of TIB (0. mg/kg, 0.01. mg/kg, 0.1. mg/kg 1.0. mg/kg and 10. mg/kg, administered daily via the oral route for 18. weeks). Two behavioral animal models, the autoshaping and T maze models were employed. The concentrations of acetyl choline transferase (ChAT) and tryptophan hydroxylase (TPH) in the hippocampus were directly measured by Western blot. No significant changes were observed in the autoshaping model and spontaneous activity test. In the T maze, increased latency was observed with TIB doses of 1 and 10. mg/kg compared to the vehicle. We observed that the ChAT content decreased with increasing doses of TIB, whereas TPH content increased with doses of 1 and 10. mg/kg of TIB. These data indicate that high doses of TIB improved emotional learning, which may be related to the modulation of the cholinergic and serotonergic systems by TIB.
AB - Hormone replacement therapy (HRT) may be prescribed to prevent the symptoms of menopause. This therapy may include estrogenic and/or progestin components and may increase the incidence of endometrial and breast cancers. Tibolone (TIB), which is also made up of estrogen and progestin components, is often used to reduce the impact of HRT. However, the effect of TIB on the processes of learning, memory and anxiety has yet to be fully elucidated. The aim of this study was to evaluate the long-term effect on learning, memory processes and anxiety in ovariectomized rats caused by different doses of TIB (0. mg/kg, 0.01. mg/kg, 0.1. mg/kg 1.0. mg/kg and 10. mg/kg, administered daily via the oral route for 18. weeks). Two behavioral animal models, the autoshaping and T maze models were employed. The concentrations of acetyl choline transferase (ChAT) and tryptophan hydroxylase (TPH) in the hippocampus were directly measured by Western blot. No significant changes were observed in the autoshaping model and spontaneous activity test. In the T maze, increased latency was observed with TIB doses of 1 and 10. mg/kg compared to the vehicle. We observed that the ChAT content decreased with increasing doses of TIB, whereas TPH content increased with doses of 1 and 10. mg/kg of TIB. These data indicate that high doses of TIB improved emotional learning, which may be related to the modulation of the cholinergic and serotonergic systems by TIB.
KW - Anxiety
KW - Choline acetyl transferase
KW - Hippocampus
KW - Learning
KW - Memory
KW - Tibolone
KW - Tryptophan hydroxylase
UR - http://www.scopus.com/inward/record.url?scp=84855944876&partnerID=8YFLogxK
U2 - 10.1016/j.yhbeh.2011.10.005
DO - 10.1016/j.yhbeh.2011.10.005
M3 - Artículo
SN - 0018-506X
VL - 61
SP - 76
EP - 83
JO - Hormones and Behavior
JF - Hormones and Behavior
IS - 1
ER -