Martin I, Torres Neto R, Oba E, Buratini J, Binelli M, Laufer-Amorim R, Ferreira J C P
Department of Animal Reproduction and Veterinary Radiology, School of Veterinary Medicine and Animal Science, UNESP, São Paulo, Brazil.
Reprod Domest Anim. 2008 Aug;43(4):415-21. doi: 10.1111/j.1439-0531.2007.00928.x. Epub 2007 Jan 3.
The aim of the present study was to monitor endometrial distribution and concentrations of oestrogen receptors alpha (ER alpha) and progesterone receptors (PR) by immunohistochemistry in Nelore cows (Bos taurus indicus) during the oestrous cycle. Blood samples were collected for progesterone measurement and endometrial samples were taken from the uterine horn contra lateral to the corpus luteum in 16 cows at days 0 (ovulation), 5, 9, 13 and 19 of the oestrous cycle. Immunostaining evaluation for ER alpha and PR in the glandular epithelium and uterine stroma was performed by two methods: positive nuclei counting and staining intensity of the nuclei. Specific positive staining reactions for both receptors were limited to cell nuclei and they were not identified in the cytoplasm. The proportion of ER alpha positive nuclei had a temporal variation throughout the oestrous cycle in both cell types evaluated and was higher in uterine stroma than the glandular epithelium (p < 0.05). The greatest proportion of ER alpha stained nuclei was observed at oestrus and during the initial and mid luteal phase (days 5, 9 and 13) (p < 0.05) in the glandular epithelium and at days 0, 5 and 9 in the uterine stroma (p < 0.01). The proportion of PR positive nuclei remained constant throughout the entire oestrous cycle for both cell types evaluated (p > 0.05). A higher proportion of PR positive nuclei was measured in the uterine stroma compared with the glandular epithelium (p < 0.05). Intensity of staining for ER alpha and PR varied throughout the oestrous cycle (p < 0.01). There was a higher staining intensity at days 0 and 5 in the stroma for ER alpha (p < 0.01) and PR (p < 0.01) and in the glandular epithelium at days 0, 5, 9 and 13 for ER alpha (p < 0.01) and at days 0, 5 and 9 for PR (p < 0.01) when compared with the other evaluated days. These data demonstrate that ER alpha and PR expression varied throughout the oestrous cycle in Nelore cows, in general with highest concentrations at oestrus and the lowest during the luteal phase. This is similar to patterns observed in Bos taurus taurus.
本研究的目的是通过免疫组织化学方法监测发情周期中内洛尔牛（印度瘤牛）子宫内膜中雌激素受体α（ERα）和孕激素受体（PR）的分布及浓度。在发情周期的第0天（排卵日）、第5天、第9天、第13天和第19天，采集16头母牛的血样用于测定孕酮，并从黄体对侧子宫角采集子宫内膜样本。采用两种方法对腺上皮和子宫基质中的ERα和PR进行免疫染色评估：阳性细胞核计数和细胞核染色强度。两种受体的特异性阳性染色反应均局限于细胞核，在细胞质中未发现。在所评估的两种细胞类型中，ERα阳性细胞核的比例在整个发情周期中均有时间变化，且子宫基质中的比例高于腺上皮（p<0.05）。在腺上皮中，发情期以及黄体初期和中期（第5天、第9天和第13天）观察到ERα染色细胞核的比例最高（p<0.05），在子宫基质中，第0天、第5天和第9天比例最高（p<0.01）。在所评估的两种细胞类型中，PR阳性细胞核的比例在整个发情周期中保持恒定（p>0.05）。与腺上皮相比，子宫基质中PR阳性细胞核的比例更高（p<0.05）。ERα和PR的染色强度在整个发情周期中有所变化（p<0.01）。与其他评估日相比，在第0天和第5天，基质中ERα（p<0.01）和PR（p<0.01）的染色强度更高，在第0天、第5天、第9天和第13天，腺上皮中ERα（p<0.01）的染色强度更高，在第0天、第5天和第9天，PR（p<0.01）的染色强度更高。这些数据表明，内洛尔牛发情周期中ERα和PR的表达存在变化，总体上发情期浓度最高，黄体期最低。这与普通牛中观察到的模式相似。
