title: Sex and estrous cycle-dependent differences in glial fibrillary acidic protein immunoreactivity in the adult rat hippocampus.
abstract: Sex differences in the morphology and function of the hippocampus have been reported in several species, but it is unknown whether a sexual dimorphism exists in glial fibrillary acidic protein (GFAP) expression in the rat hippocampus. We analyzed GFAP immunoreactivity in the hippocampus of intact adult male rats as well as in females during diestrus and proestrus phases of the estrous cycle. We found that in CA1, CA3, and dentate gyrus, GFAP immunoreactivity was higher in proestrus females as compared with males and diestrus females. In CA1, a similar GFAP immunoreactivity was found in males and in diestrus females, but in dentate gyrus, males presented the lowest GFAP content. Interestingly, differences in astrocyte morphology were also found. Rounded cells with numerous and short processes were mainly observed in the hippocampus during proestrus whereas cells with stellate shape with few and long processes were present in the hippocampus of males and diestrus females. The marked sex and estrous cycle-dependent differences in GFAP immunoreactivity density and in astrocyte number and morphology found in the rat hippocampus, suggest the involvement of sex steroid hormones in the sexually dimorphic functions of the hippocampus, and in the change in its activity during the estrous cycle.
authors.affiliation: Departamento de Medicina Genómica y Toxicología Ambiental, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Mexico.
authors.forename: Clorinda
authors.initials: C
authors.lastname: Arias
authors.forename: Angélica
authors.initials: A
authors.lastname: Zepeda
authors.forename: Karina
authors.initials: K
authors.lastname: Hernández-Ortega
authors.forename: Perla
authors.initials: P
authors.lastname: Leal-Galicia
authors.forename: Cinthia
authors.initials: C
authors.lastname: Lojero
authors.forename: Ignacio
authors.initials: I
authors.lastname: Camacho-Arroyo
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D001253:Astrocytes / Q000166:cytology / Q000502:physiology; D048430:Cell Shape; D004031:Diestrus; D030762:Estrous Cycle / Q000502:physiology*; D005455:Fluorescent Antibody Technique; D005904:Glial Fibrillary Acidic Protein / Q000378:metabolism*; D006624:Hippocampus / Q000166:cytology / Q000502:physiology*; D008297:Male; D011359:Proestrus; D051381:Rats; D017208:Rats, Wistar; D012727:Sex Characteristics
chemical_list: D005904:Glial Fibrillary Acidic Protein