Immunohistochemical analysis of the hypothalamic-pituitary-adrenal axis in dogs: sex-linked and seasonal variation

QUIROGA, A; VISSIO, P; LOMBARDO, D A. MEIKLE, V. A. CASTILLO; SOLER ARIAS, E; CASTILLO V; GALLELLI, M.F; CAGGIANO, N; MEIKLE, A

RESEARCH IN VETERINARY SCIENCE

ELSEVIER SCI LTD

Lugar: Amsterdam; Año: 2016 vol. 104 p. 10 - 16

0034-5288

dogs, as well as the expression of oestrogen receptor alpha (ERα). An immunohistochemical analysis was conducted in pituitaries for ACTH and in adrenal glands for ERα and for themelanocortin-2-receptor (MC2R) in winter and summer. Double immunofluorescence was performed to identify ERα in corticotrophs. Females had a  greater proportion of corticotrophs per field (p b 0.01), with a greater cellular area and optical density (p <0.001) than males. Optical density of corticotrophs was greater in winter for both sexes (p < 0.001). In zona fasciculata, ERα and MC2R expression was greater in females (p < 0.001) and was greater in winter (p<0.001). ERα was identified in corticotrophs. This study is the first to demonstrate ERα expression in corticotrophs and the adrenal cortex in dogs, providing evidence for sexual dimorphism and seasonal variations.