TY - JOUR
T1 - Localization of orexin B and orexin-2 receptor in the rat epididymis
AU - Liguori, Giovanna
AU - Tafuri, Simona
AU - Miyoshi, Chika
AU - Yanagisawa, Masashi
AU - Squillacioti, Caterina
AU - De Pasquale, Valeria
AU - Mirabella, Nicola
AU - Vittoria, Alfredo
AU - Costagliola, Anna
N1 - Funding Information:
The Merck Millipore is deeply acknowledged for the kind gift of the anti-OX2R antibody used in this study. Mr. Antonio Calamo and Dr. Emma Cirillo are acknowledged as well for the technical support and the administrative work, respectively. The research was in part supported by the World Premier International Research Center Initiative from MEXT, Japan (to MY, CM).
Publisher Copyright:
© 2018 Elsevier GmbH
PY - 2018/4
Y1 - 2018/4
N2 - The peptides orexin A (OXA) and orexin B (OXB) derived from the proteolytic cleavage of a common precursor molecule, prepro-orexin, were originally described in the rat hypothalamus. Successively, they have been found in many other brain regions as well as in peripheral organs of mammals and other less evolved animals. The widespread localization of orexins accounts for the multiple activities that they exert in the body, including the regulation of energy homeostasis, feeding, metabolism, sleep and arousal, stress, addiction, and cardiovascular and endocrine functions. Both OXA and OXB peptides bind to two G-coupled receptors, orexin-1 (OX1R) and orexin-2 (OX2R) receptor, though with different binding affinity. Altered expression/activity of orexins and their receptors has been associated with a large number of human diseases. Though at present evidence highlighted a role for orexins and cognate receptors in mammalian reproduction, their central and/or local effects on gonadal functions remain poorly known. Here, we investigated the localization of OXB and OX2R in the rat epididymis. Immunohistochemical staining of sections from caput, corpus and cauda segments of the organ showed intense signals for both OXB and OX2R in the principal cells of the lining epithelium, while no staining was detected in the other cell types. Negative results were obtained from immunohistochemical analysis of hypothalamic and testicular tissues from OX2R knock-out mice (OX2R −/− ) and OX1R/OX2R double knock-out (OX1R −/− ; OX2R −/− ) mice, thus demonstrating the specificity of the rabbit polyclonal anti-OX2R antibody used in our study. On contrary, the same antibody clearly showed the presence of OX2R in sections from hypothalamus and testis of normal mice and rats which are well known to express the receptor. Thus, our results provide the first definite evidence for the immunohistochemical localization of OXB and OX2R in the principal cells of rat epididymis.
AB - The peptides orexin A (OXA) and orexin B (OXB) derived from the proteolytic cleavage of a common precursor molecule, prepro-orexin, were originally described in the rat hypothalamus. Successively, they have been found in many other brain regions as well as in peripheral organs of mammals and other less evolved animals. The widespread localization of orexins accounts for the multiple activities that they exert in the body, including the regulation of energy homeostasis, feeding, metabolism, sleep and arousal, stress, addiction, and cardiovascular and endocrine functions. Both OXA and OXB peptides bind to two G-coupled receptors, orexin-1 (OX1R) and orexin-2 (OX2R) receptor, though with different binding affinity. Altered expression/activity of orexins and their receptors has been associated with a large number of human diseases. Though at present evidence highlighted a role for orexins and cognate receptors in mammalian reproduction, their central and/or local effects on gonadal functions remain poorly known. Here, we investigated the localization of OXB and OX2R in the rat epididymis. Immunohistochemical staining of sections from caput, corpus and cauda segments of the organ showed intense signals for both OXB and OX2R in the principal cells of the lining epithelium, while no staining was detected in the other cell types. Negative results were obtained from immunohistochemical analysis of hypothalamic and testicular tissues from OX2R knock-out mice (OX2R −/− ) and OX1R/OX2R double knock-out (OX1R −/− ; OX2R −/− ) mice, thus demonstrating the specificity of the rabbit polyclonal anti-OX2R antibody used in our study. On contrary, the same antibody clearly showed the presence of OX2R in sections from hypothalamus and testis of normal mice and rats which are well known to express the receptor. Thus, our results provide the first definite evidence for the immunohistochemical localization of OXB and OX2R in the principal cells of rat epididymis.
KW - Epididymis
KW - Orexin B
KW - Orexin-2 receptor
KW - Rat
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U2 - 10.1016/j.acthis.2018.02.011
DO - 10.1016/j.acthis.2018.02.011
M3 - Article
C2 - 29496265
AN - SCOPUS:85042487010
SN - 0065-1281
VL - 120
SP - 292
EP - 297
JO - Acta Histochemica
JF - Acta Histochemica
IS - 3
ER -