title: Effects of an anabolic steroid (Durateston) on testicular angiogenesis in peripubertal stallions.
abstract: The aim of this study was to determine the effect of the anabolic steroid testosterone on the testicular vascularization, angiogenesis and expression of angiogenic factors, and their receptors in testes of peripubertal stallions. Seven peripubertal stallions were treated with Durateston and castrated either 4 (treatment group 1 [TG1]) or 12 weeks (TG2) after the last injection. The castration of seven untreated control stallions (control group [CG]) took place within the same time. In the testicular specimens, volume density (VD), numerical density (ND), and area of vessels were determined morphometrically. Immunohistochemically, the expression of vascular endothelial growth factor (VEGF) and its receptor VEGF-R2; angiopoietin 2 (Ang2) and its receptor Tie2 as well as of transforming growth factor α (TGF-α) was investigated. Morphometrically, the VD of TG1 (P = 0.000) and TG2 (P = 0.001) vessels and the ND of arterioles and venules and capillaries were higher (TG1, TG2: P < 0.05), and the area of capillary cross sections was smaller (TG1, TG2: P < 0.05) than that in the CG. Compared to TG2 horses, TG1 animals showed a higher (P < 0.05) VD and ND of vascular structures and a smaller (P < 0.05) area of capillary cross sections. In numerous vascular structures, especially of TG1, the TGF-α and, to a less extent, the Ang2 and VEGF-R2 expression was significantly higher (P < 0.05) than that in the CG. Sertoli cells in TG2 were characterized by a significantly higher expression (P < 0.05) of VEGF-R2 than in the CG. In summary, the most and smallest vessels could be detected in the testes of TG1. Most likely this is explainable by the highest expression of some angiogenic factors (TGF-α, Ang2) and receptors (VEGF-R2) investigated. This expression behavior may be stimulated by testosterone. As a significant decrease of morphometric parameters could be detected in TG2 compared to TG1, the stimulatory effect of testosterone seems to be temporary.
authors.affiliation: Institute of Pathology, Faculty of Veterinary Medicine, University of Leipzig, Leipzig, Germany. Electronic address: anja.teubner@gmx.de.
authors.forename: A
authors.initials: A
authors.lastname: Teubner
authors.affiliation: Institute of Pathology, Faculty of Veterinary Medicine, University of Leipzig, Leipzig, Germany.
authors.forename: K
authors.initials: K
authors.lastname: Müller
authors.affiliation: Clinic for Horses, University of Veterinary Medicine Hannover, Foundation, Hannover, Germany.
authors.forename: C P
authors.initials: CP
authors.lastname: Bartmann
authors.affiliation: Clinic for Horses, Unit for Reproductive Medicine, University of Veterinary Medicine Hannover, Foundation, Hannover, Germany.
authors.forename: H
authors.initials: H
authors.lastname: Sieme
authors.affiliation: Clinic for Horses, Unit for Reproductive Medicine, University of Veterinary Medicine Hannover, Foundation, Hannover, Germany.
authors.forename: E
authors.initials: E
authors.lastname: Klug
authors.affiliation: Clinic for Horses, Unit for Reproductive Medicine, University of Veterinary Medicine Hannover, Foundation, Hannover, Germany.
authors.forename: B
authors.initials: B
authors.lastname: Zingrebe
authors.affiliation: Institute of Pathology, Faculty of Veterinary Medicine, University of Leipzig, Leipzig, Germany.
authors.forename: H-A
authors.initials: HA
authors.lastname: Schoon
mesh_terms: D045930:Anabolic Agents / Q000494:pharmacology*; D000818:Animals; D006736:Horses / Q000502:physiology*; D007150:Immunohistochemistry; D008297:Male; D018919:Neovascularization, Physiologic / Q000187:drug effects*; D040262:Receptors, Vascular Endothelial Growth Factor / Q000378:metabolism; D012741:Sexual Maturation; D013737:Testis / Q000098:blood supply* / Q000473:pathology; D013739:Testosterone / Q000378:metabolism / Q000494:pharmacology*; D042442:Vascular Endothelial Growth Factors / Q000378:metabolism
chemical_list: D045930:Anabolic Agents; D042442:Vascular Endothelial Growth Factors; D013739:Testosterone; D040262:Receptors, Vascular Endothelial Growth Factor
keywords: Anabolic steroid; Angiogenesis; Stallion; Testis; Testosterone