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

GALLELLI, MARÍA FLORENCIA; LOMBARDO, D; VISSIO, PAULA; QUIROGA, A; CAGGIANO, N; SOLER, E; MEIKLE, A; CASTILLO, VA

RESEARCH IN VETERINARY SCIENCE

ELSEVIER SCI LTD

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

0034-5288

This study evaluated sexual dimorphism and seasonal variations in corticotrophs and adrenal zona fasciculata indogs, as well as the expression of oestrogen receptor alpha (ERα). An immunohistochemical analysis was conductedin pituitaries for ACTH and in adrenal glands for ERα and for the melanocortin-2-receptor (MC2R) in winterand summer. Double immunofluorescence was performed to identify ERα in corticotrophs. Females had agreater proportion of corticotrophs per field (p b 0.01), with a greater cellular area and optical density (p b0.001) than males. Optical density of corticotrophs was greater in winter for both sexes (p b 0.001). In zonafasciculata, ERα and MC2R expression was greater in females (p b 0.001) and was greater in winter (p b0.001). ERα was identified in corticotrophs. This study is the first to demonstrate ERα expression in corticotrophsand the adrenal cortex in dogs, providing evidence for sexual dimorphism and seasonal variations