Immunohistochemical imaging of kisspeptin in some brain regions in different stages of sexual cycles of female mice

The aim of the study was to determine kisspeptin intensity by immunofluorescence method in hypothalamus arcuate nucleus (ARC), paraventricular nucleus (PVN), dorsomedial nucleus (DMN) and ventromedial nucleus (VMN) in the diestrus, proestrus and estrus phases of the sexual stages of female mice. The other purpose of this study was to determine the physiological mechanisms of the kisspeptin secretions determined by the immunofluorescence method in these hypothalamic regions of the female mice during the sexual periods and to introduce the immunofluorescence imaging of these regions into the literature. With the study conducted in accordance with the specified purpose, the presence of kisspeptin expression in different oestrus phases in brain tissue was determined by immunofluorescence method and the relationship between kisspeptin expression and physiological mechanisms affected by kisspeptin secreting brain regions was investigated. In this study, totally 40 Balb/c female mice with 5-6 months age and average weight of 35-40 grams were used. Vaginal smears were taken between 10.00-12.00 hours during 15 days in all female mice. A total of 21 animals with regular cycles were then selected and divided into 3 groups according to the oestrus phases (diestrus, proestrus and oestrus groups, n = 7). The animals in the diestrus, proestrus and oestrus phases were decapitated without administration of any anesthetic, and then brain tissues were frozen on dry ice. Sections were taken from brain tissue and fluorescence staining steps were applied. At the end of the study, the intensity of kisspeptin in ARC, PVN, DMN and VMN nuclei of hypothalamus was calculated. It was found that the intensity of kisspeptin increased significantly in the oestrus group compared to the diestrus group in ARC. When the intensity of kisspeptin in the PVN was statistically evaluated, no significant difference was found among the groups. In the DMN and VMN regions, when the estrus and proestrus groups were compared to the diestrus group, the intensity of kisspeptin increased significantly. As a result, it was determined that kisspeptin intensity was different in hypothalamic ARC, DMN, VMN and PVN regions at estrous, diestrus and proestrus stages of female mice.