Wang Di, Cheng Xiumei, Fang Huimin, Ren Yanqing, Li Xinhua, Ren Weiwei, Xue Bing, Yang Cairui
Hebei University of Chinese Medicine, No.326, Xinshi South Road, Qiaoxi District, Shijiazhuang, 050091, Hebei Province, China.
Reprod Biol Endocrinol. 2020 Apr 14;18(1):29. doi: 10.1186/s12958-020-00584-1.
Cold, an environmental factor, induces many reproductive diseases. It is known that endothelin (ET) is a potent vasoconstrictor, and cold stress can increase the expression of ET and its receptors. The cold stress rat model was developed to examine two parameters: (1) the effects of cold stress on ovarian and uterine morphology, function, and microvascular circulation and (2) possible mechanisms of ET and its receptors involved in cold stress-induced menstruation disorders.
The rat cold stress model was prepared with an ice water bath. The estrous cycle was observed by methylene blue and hematoxylin and eosin (H&E) staining. Serum estradiol 2 (E), testosterone (T), progesterone (P) were detected by radioimmunoassay. Hemorheology indices were measured. The real-time blood flow of auricle and uterine surfaces was measured. Expressions of CD34 and α-SMA in ovarian and uterine tissues were detected by immunohistochemistry. ET-1 contents in serum were tested, and expressions of ET-receptor types A and B (ET-AR and ET-BR) in ovarian tissues were detected via Western blotting.
Cold stress extended the estrous cycle, thereby causing reproductive hormone disorder, imbalance of local endothelin/nitric oxide expression, and microcirculation disturbance. Cold-stress led to up-regulation of ET-AR expression and protein and down-regulation of ET-BR expression in rats.
This study suggests that the reason for cold stress-induced dysfunction in reproductive organs may be closely related to the imbalance of ET-1 and its receptor expressions, leading to microvascular circulation disorders in local tissues.
寒冷作为一种环境因素，可诱发多种生殖系统疾病。已知内皮素（ET）是一种强效血管收缩剂，冷应激可增加ET及其受体的表达。本研究建立了冷应激大鼠模型，以检测两个参数：（1）冷应激对卵巢和子宫形态、功能及微循环的影响；（2）ET及其受体参与冷应激诱导月经紊乱的可能机制。
采用冰水浴制备大鼠冷应激模型。通过亚甲蓝及苏木精-伊红（H&E）染色观察动情周期。采用放射免疫法检测血清雌二醇2（E）、睾酮（T）、孕酮（P）水平。检测血液流变学指标。测量耳廓和子宫表面的实时血流量。采用免疫组织化学法检测卵巢和子宫组织中CD34和α-SMA的表达。检测血清中ET-1含量，并通过蛋白质印迹法检测卵巢组织中A型和B型ET受体（ET-AR和ET-BR）的表达。
冷应激使动情周期延长，进而导致生殖激素紊乱、局部内皮素/一氧化氮表达失衡及微循环障碍。冷应激导致大鼠ET-AR表达及蛋白上调，ET-BR表达下调。
本研究提示，冷应激导致生殖器官功能障碍的原因可能与ET-1及其受体表达失衡密切相关，进而导致局部组织微循环障碍。
