Herrera-Luna C V, Budik S, Aurich C
Centre for Artificial Insemination and Embryo Transfer, University of Veterinary Sciences, Vienna, Austria.
Reprod Domest Anim. 2012 Dec;47(6):928-35. doi: 10.1111/j.1439-0531.2012.01993.x. Epub 2012 Feb 15.
Glucocorticoids (GCs) are important mediators of the stress response and have been implicated in the function and regulation of testicular functions in different species. In many tissues, intracellular glucocorticoid activity is controlled by either or both of the two known isoforms of 11β-hydroxysteroid dehydrogenase (11βHSD) type 1 and 2, which interconvert active and inactive GCs. Little is known about the effects of stress on fertility in the equine species. The main objective of the present study was to investigate the expression of receptors for GCs and adrenocorticotropic hormone [ACTH, melanocortin 2 receptor (MC2R)] as well 11βHSD1 and 11βHSD2 in male equine epididymal and testicular tissue. In addition, expression of aromatase P-450 and receptors for luteinizing hormone (LHR), follicle stimulating hormone (FSHR) and growth hormone (GHR) was studied. Reverse transcriptase PCR and quantitative real-time PCR were performed in tissue from the epididymis (caput and cauda) and testes collected from nine healthy mature stallions (age 4-10 years). mRNA for ACTH and GC receptors as well as 11βHSD1 and -2 were found in epididymal and testicular tissue. Expression of the genes studied was always positive in testicular tissue, while it was inconsistent in epididymal tissue. Quantitative gene expression in relation to β-actin and glyceraldehyde-3-phosphate dehydrogenase (GAPDH) was significantly correlated (R = 0.403, p < 0.001). Quantitative PCR in relation to β-actin revealed significant differences in the gene expression of 11βHSD1, 11βHSD2, LHR, FSHR, MC2R and aromatase between tissue collected from caput epididymidis, cauda epididymidis and testicular parenchyma (p < 0.05). With GAPDH, differences between tissues were significant for 11βHSD1, 11βHSD2 and MC2R (p < 0.05) In addition, high concentrations of mRNA of aromatase and receptors of LH and FSH were found in testicular tissue, while a pronounced expression of GH receptor was present in epididymal tissue. The results support the hypothesis of an interaction between the pituitary-adrenal axis and testicular function in the stallion.
糖皮质激素（GCs）是应激反应的重要介质，并且与不同物种睾丸功能的作用和调节有关。在许多组织中，细胞内糖皮质激素活性由11β-羟基类固醇脱氢酶（11βHSD）1型和2型这两种已知同工型中的一种或两种控制，它们可使活性和非活性糖皮质激素相互转化。关于应激对马属动物繁殖力的影响知之甚少。本研究的主要目的是调查雄性马附睾和睾丸组织中糖皮质激素受体、促肾上腺皮质激素[ACTH，黑皮质素2受体（MC2R）]以及11βHSD1和11βHSD2的表达。此外，还研究了芳香化酶P-450以及促黄体生成素（LHR）、促卵泡激素（FSHR）和生长激素（GHR）受体的表达。对从9匹健康成熟种马（4至10岁）采集的附睾（头段和尾段）和睾丸组织进行逆转录PCR和定量实时PCR。在附睾和睾丸组织中发现了ACTH和糖皮质激素受体以及11βHSD1和-2的mRNA。所研究基因的表达在睾丸组织中始终为阳性，而在附睾组织中则不一致。与β-肌动蛋白和甘油醛-3-磷酸脱氢酶（GAPDH）相关的定量基因表达显著相关（R = 0.403，p < 0.001）。与β-肌动蛋白相关的定量PCR显示，附睾头段、附睾尾段和睾丸实质采集的组织之间，11βHSD1、11βHSD2、LHR、FSHR、MC2R和芳香化酶的基因表达存在显著差异（p < 0.05）。以GAPDH为参照，组织间11βHSD1、11βHSD2和MC2R存在显著差异（p < 0.05）。此外，在睾丸组织中发现了高浓度的芳香化酶以及LH和FSH受体的mRNA，而附睾组织中存在明显的GH受体表达。这些结果支持了种马垂体-肾上腺轴与睾丸功能之间存在相互作用的假说。
