Localization of orexin B and receptor 2 for orexins in testicular cytotypes of the camelid alpaca (Vicugna pacos).
The orexins A (OxA) and B (OxB) are two hypothalamic peptides involved in many physiological functions of the mammalian body. They act through the binding of two G-coupled receptors named receptor 1 (OX1) and receptor 2 (OX2) for orexins. The first receptor is specific for OxA, while the second binds both the substances with equal affinity. The orexins and the relative receptors have been traced by means of different techniques also at the periphery of the body and particularly in the adrenals, and in gastrointestinal and genital organs. Aim of this work was to investigate the presence of OxB and OX2by means of immunohistochemistry and Western blotting analysis in the testis of the South American camelid alpaca, a species primarily breed in Chile and Ecuador and recently diffused in Europe where the quality of its wool is particularly appreciated. OxB immunoreactivity (IR) was found in the tubular compartment of the testis where spermatogonia (resting), zygotene and pachytene spermatocytes, and spermatids clearly showed differently sized and shaped cytoplasmic positive structures. OX2-IR was found both in the interstitial and tubular compartments of the testis and particularly in Leydig cells and round and elongated spermatids. Western blotting analysis of testis lysates showed the presence of a protein band whose molecular weight corresponded to that currently assigned to OX2. Such findings easily translate the hypothesis that OxB and its receptor 2 play a functional role both in the interstitial and tubular compartments of the alpaca testis.
Department of Veterinary Medicine and Animal Productions, University of Naples Federico II, Naples, Italy.
G
G
Liguori
Department of Veterinary Medicine and Animal Productions, University of Naples Federico II, Naples, Italy.
C
C
Squillacioti
Department of Biology, University of Naples Federico II, Naples, Italy.
L
L
Assisi
Department of Veterinary Medicine and Animal Productions, University of Naples Federico II, Naples, Italy.
N
N
Mirabella
School of Agricultural, Forestry, Food and Environmental Sciences, University of Basilicata, Potenza, Italy.
E
E
Langella
Department of Veterinary Medicine and Animal Productions, University of Naples Federico II, Naples, Italy.
A
A
Costagliola
Department of Veterinary Medicine and Animal Productions, University of Naples Federico II, Naples, Italy.
A
A
Vittoria
D000818:Animals; D002161:Camelids, New World / Q000378:metabolism*; D007150:Immunohistochemistry; D007985:Leydig Cells / Q000378:metabolism; D008297:Male; D064446:Orexin Receptors / Q000378:metabolism*; D000068797:Orexins / Q000378:metabolism*; D013087:Spermatids / Q000378:metabolism; D013093:Spermatogonia / Q000378:metabolism; D013737:Testis / Q000166:cytology / Q000378:metabolism*; D014018:Tissue Distribution
D064446:Orexin Receptors; D000068797:Orexins
alpaca; orexin B; receptor 2 for orexins; testis