TY - JOUR
TI - Effects of testosterone and estradiol on stress-induced adrenal and hippocampal weight changes in female rats
AU - Sfikakis, A.
AU - Pitychoutis, P.M.
AU - Tsouma, A.
AU - Messari, I.
AU - Papadopoulou-Daifoti, Z.
JO - Vitamins and Hormones
PY - 2014
VL - 13
TODO - 1
SP - 119-130
PB - Hellenic Endocrine Society
SN - null
TODO - 10.1007/bf03401327
TODO - estradiol;  estradiol benzoate;  testosterone;  estradiol;  testosterone, adrenal gland;  animal experiment;  animal tissue;  article;  chronic stress;  controlled study;  emotional reactivity score;  emotional stress;  estrus;  female;  hippocampus;  hormone action;  nonhuman;  organ weight;  ovariectomy;  prevalence;  proestrus;  radioimmunoassay;  rat;  scoring system;  testosterone blood level;  thymus;  vagina smear;  adrenal gland;  adrenalectomy;  animal;  drug effects;  hippocampus;  mental stress;  organ size;  pathology;  Wistar rat, Adrenal Glands;  Adrenalectomy;  Animals;  Estradiol;  Female;  Hippocampus;  Organ Size;  Ovariectomy;  Rats;  Rats, Wistar;  Stress, Psychological;  Testosterone
TODO - 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.
ER -