title: Functional morphology of pituitary -thyroid and -adrenocortical axes in middle-aged male rats treated with Vitex agnus castus essential oil.
abstract: We previously reported that Vitex agnus-castus L. essential oil (VACEO), when administered to middle-aged males, exerts a bone-protective effect, induces silencing of locomotor activities and decreases pituitary prolactin immunopositivity. To further assess the putative endocrine effects of VACEO, we examined the pituitary-thyroid and -adrenocortical axes in our model. Sixteen-month-old Wistar rats were subcutaneously administered 60mg/kg of VACEO dissolved in sterile olive oil, while the control group received the same amount of vehicle alone for three weeks. Pituitaries, thyroids and adrenals were analyzed by qualitative and quantitative histological approaches. Concentration of thyroid stimulating hormone (TSH), total thyroxine and triiodothyronine (TH), adrenocorticotrophic hormone (ACTH), corticosterone in serum and in adrenal tissue were measured. In VACEO-treated rats, the relative volume density of pituitary thyrotrophs increased (p<0.001), while intensity of cytoplasmic TSHβ immunostaining decreased (p<0.001), consistent with elevated TSH in serum (p<0.01). The thyroid tissue was characterized by a micro-follicular structure, increased relative volume of follicular epithelium (p<0.05), decreased volume of luminal colloid (p<0.001) and increased basolateral expression of sodium-iodide symporter-immunopositivity (p<0.05). Serum TH also increased (p<0.01). The relative volume density of pituitary corticotrophs decreased (p<0.05), compatible with decline in circulating ACTH (p<0.05). Neither tissue nor serum corticosterone levels were affected by VACEO treatment. In conclusion, the observed changes in TSH and ACTH strongly indicate central endocrine effects of prolonged VACEO treatment. In this respect, production of ACTH decreased without impact on corticosterone production. Increase in serum concentration of both TH and TSH are not compatible with a negative feedback loop and suggest a major change in set-point regulation of the hypothalamic-pituitary-thyroid axis.
authors.affiliation: Institute for Biological Research "Siniša Stanković'', University of Belgrade, Despot Stefan Blvd. 142, 11060, Belgrade, Serbia. Electronic address: brankasj@ibiss.bg.ac.rs.
authors.forename: Branka
authors.initials: B
authors.lastname: Šošić-Jurjević
authors.affiliation: Institute for Biological Research "Siniša Stanković'', University of Belgrade, Despot Stefan Blvd. 142, 11060, Belgrade, Serbia.
authors.forename: Vladimir
authors.initials: V
authors.lastname: Ajdžanović
authors.affiliation: Institute for Biological Research "Siniša Stanković'', University of Belgrade, Despot Stefan Blvd. 142, 11060, Belgrade, Serbia.
authors.forename: Branko
authors.initials: B
authors.lastname: Filipović
authors.affiliation: Institute for Biological Research "Siniša Stanković'', University of Belgrade, Despot Stefan Blvd. 142, 11060, Belgrade, Serbia.
authors.forename: Svetlana
authors.initials: S
authors.lastname: Trifunović
authors.affiliation: Institute for Biological Research "Siniša Stanković'', University of Belgrade, Despot Stefan Blvd. 142, 11060, Belgrade, Serbia.
authors.forename: Ivana
authors.initials: I
authors.lastname: Jarić
authors.affiliation: Institute for Biological Research "Siniša Stanković'', University of Belgrade, Despot Stefan Blvd. 142, 11060, Belgrade, Serbia.
authors.forename: Nataša
authors.initials: N
authors.lastname: Ristić
authors.affiliation: Institute for Biological Research "Siniša Stanković'', University of Belgrade, Despot Stefan Blvd. 142, 11060, Belgrade, Serbia.
authors.forename: Verica
authors.initials: V
authors.lastname: Milošević
mesh_terms: D000324:Adrenocorticotropic Hormone / Q000378:metabolism; D000375:Aging; D000818:Animals; D001835:Body Weight / Q000187:drug effects*; D008297:Male; D009822:Oils, Volatile / Q000494:pharmacology*; D009929:Organ Size / Q000187:drug effects*; D010902:Pituitary Gland / Q000166:cytology / Q000187:drug effects*; D017208:Rats, Wistar; D027981:Symporters / Q000187:drug effects; D013961:Thyroid Gland / Q000187:drug effects* / Q000378:metabolism; D013972:Thyrotropin / Q000097:blood; D013974:Thyroxine / Q000097:blood; D020950:Vitex / Q000187:drug effects*; D000099209:Sodium-Iodide Symporters
chemical_list: D000324:Adrenocorticotropic Hormone; D009822:Oils, Volatile; D027981:Symporters; D013972:Thyrotropin; D013974:Thyroxine; D000099209:Sodium-Iodide Symporters
keywords: Adrenal; Pituitary; Rats; Thyroid; Vitex agnus-castus essential oil