Effects of testosterone and estradiol on stress-induced adrenal and hippocampal weight changes in female rats.

Autor: Sfikakis A; Department of Pharmacology, Medical School, National & Kapodistrian University of Athens, Athens, Greece., Pitychoutis PM; Department of Biology & Center for Tissue Regeneration and Engineering (TREND), University of Dayton, Dayton, USA., Tsouma A; Department of Pharmacology, Medical School, National & Kapodistrian University of Athens, Athens, Greece., Messari I; Department of Pharmacology, Medical School, National & Kapodistrian University of Athens, Athens, Greece., Papadopoulou-Daifoti Z; Department of Pharmacology, Medical School, National & Kapodistrian University of Athens, Athens, Greece.
Jazyk: angličtina
Zdroj: Hormones (Athens, Greece) [Hormones (Athens)] 2014 Jan-Mar; Vol. 13 (1), pp. 119-30.
DOI: 10.1007/BF03401327
Abstrakt: Objective: To examine the impact of circulating testosterone (T) and the T/Estradiol (T/Ediol) ratio on chronic stress-induced changes of adrenal and hippocampal weight during proestrus (PE) and estrus (E) in female rats.
Design: Stress was composed of repeated vaginal smear screening (VSS) and measured by the emotional reactivity score (ERS). Adrenal and hippocampal weight and the T, Ediol and T/Ediol ratio were assessed in PE and E controls as well as 20 h after sham or left adrenalectomy performed on diestrus-2 (DE-2) and PE, respectively. T was measured in ovariectomized (OVX) rats treated with estradiol benzoate (EB) or vehicle (VEH) and in non-OVX EB-treated rats.
Results: In OVX rats EB treatment increased adrenal weight and T levels. After separation of VEH- and EB-treated rats into the low and high T-range (below and above the mean, respectively), it was observed that higher T was accompanied by higher adrenal weight in EB- compared to VEH-treated rats only in the low T-range. Non-OVX EB-treated rats with high T had lower adrenal weight compared to low T. Cycling rats assigned to the high T-range presented higher T/Ediol ratio but similar ERS and Ediol levels compared to rats in the low T-range, and were characterized by reduced adrenal weight, higher hippocampal weight and prevalence of PE versus E.
Conclusions: High T and high T/Ediol ratios are prominent in PE compared to E and exert a protective effect on hippocampal neuronal degeneration after similar chronic stress through T-mediated lessening of stress response thus counteracting the stress-promoting effects of Ediol.
Databáze: MEDLINE
Externí odkaz: