Immunohistochemical characterization of the arcuate kisspeptin/ neurokinin b/dynorphin (KNDy) and preoptic kisspeptin neuronal populations in the hypothalamus during the estrous cycle in heifers

Ahmed Saad Ahmed Hassaneen, Yousuke Naniwa, Yuta Suetomi, Shuichi Matsuyama, Koji Kimura, Nahoko Ieda, Naoko Inoue, Yoshihisa Uenoyama, Hiroko Tsukamura, Kei Ichiro Maeda, Fuko Matsuda, Satoshi Ohkura

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14 Citations (Scopus)


Elucidating the physiological mechanisms that control reproduction is an obvious strategy for improving the fertility of cattle and developing new agents to control reproductive functions. The present study aimed to identify kisspeptin neurons in the bovine hypothalamus, clarifying that a central mechanism is also present in the cattle brain, as kisspeptin is known to play an important role in the stimulation of gonadotropin-releasing hormone (GnRH)/gonadotropin secretion in other mammals. To characterize kisspeptin neurons in the bovine hypothalamus, the co-localizations of kisspeptin and neurokinin B (NKB) or kisspeptin and dynorphin A (Dyn) were examined. Hypothalamic tissue was collected from Japanese Black or Japanese Black × Holstein crossbred cows during the follicular and luteal phases. Brain sections, including the arcuate nucleus (ARC) and the preoptic area (POA), were dual immunostained with kisspeptin and either NKB or Dyn. In the ARC, both NKB and Dyn were co-localized in kisspeptin neurons during both the follicular and luteal phases, demonstrating the presence of kisspeptin/NKB/Dyn-containing neurons, referred to as KNDy neurons, in cows. In the POA, no co-localization of kisspeptin with either NKB or Dyn was detected. Kisspeptin expression in the follicular phase was higher than that in the luteal phase, suggesting that kisspeptin expression in the POA is positively controlled by estrogen in cows. The kisspeptin neuronal populations in the ARC and POA likely play important roles in regulating the GnRH pulse and surge, respectively, in cows.

Original languageEnglish
Pages (from-to)471-477
Number of pages7
JournalJournal of Reproduction and Development
Issue number5
Publication statusPublished - 2016



  • Estrogen
  • Estrous cycle
  • Heifers
  • Immunohistochemistry
  • KNDy

ASJC Scopus subject areas

  • Animal Science and Zoology

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