甲状腺功能减退对雄性大鼠睾丸c-fos和c-jun基因mRNA表达的影响

Effect of hypothyroidism on c-fos and c-jun mRNA expression in testes of rats

目的探讨甲状腺功能减退（简称甲减）对雄性大鼠睾丸c-fos和c-jun基因mRNA表达的影响，为碘缺乏病的防治提供理论依据。方法健康Wistar雄性大鼠20只，按体质量（200—240g）采用随机数字表法分为2组：对照组（生理盐水组，1ml／100g）和甲状腺功能减退组（甲减组，0．1％丙硫氧嘧啶1ml／100g），每组10只，灌胃60d，每3天称体质量1次，调整灌胃剂量。灌胃结束次日处死大鼠，放射免疫法检测血清中甲状腺激素水平，包括总三碘甲状腺素原氨酸（TT3）、总甲状腺素（TT4）、促甲状腺激素（TSH）；实时定量PCR技术检测睾丸组织c-fos和c-jun基因mRNA表达水平。结果灌胃第30、60天，甲减组大鼠体质量[（239．00±15．02）、（232．67±17．86）g]均低于对照组[（298．20±12．15）、（344．00±13．73）g，t=7．704、11．380，P均〈0．05]。灌胃60d，甲减组大鼠凡[（373．32±101．31）ng／L]、IT4[（4．00±0．89）×10^3ng／L]均低于对照组[（1000．01±273．53）ng／L、（44．33±7．84）×10^3ng／L，t=5．262、12．520，P均〈0．05]；TSH[（5．77±0．89）×10^3U／L]高于对照组[（1．87±0．70）×10^3U／L，t=8．413，P〈0．05]。甲减组c-fos、c-jun基因mRNA表达（0．67±0．03、0．75±0．02）均低于对照组（1．00±0．08、1．01±0．04，t=12．382、13．784，P均〈0．05）。结论甲减可以影响雄性大鼠睾丸组织c-fos和c-jun基因mRNA表达水平，进而损伤雄性大鼠生殖系统。

Objective This study aims to define the effects of hypothyroidism on c-fos and c-jun mRNA expression in rat testes to provide a theoretical basis for prevention and control of iodine deficiency disorders （IDD）. Methods According to body weight （200 - 240 g）, 20 Wistar male rats were divided into control group and hypothyroidism group （1 ml/100 g, 0.1% propylthiouracil by intragastric administration） by digital table. There were 10 male rats in each group and body weight was observed every 3 days. After 60 days, all rats were killed. The levels of thyroid hormones [total triiodothyronine （TT3）, total thyroxine （TT4）, and thyroid stimulating hormone （TSH）] were measured by radioimmunoassay. The mRNA expression levels of c-fos and c-jun in testes were detected by real-time quantitative PCR. Results Compared with control groups [（298.20 ± 12.15）, （344.00 ± 13.73） g], the weights of hypothyroidism groups in 30 days [（239.00 ± 15.02） g] and in 60 days [（232.67 ± 17.86） g] were significant decreased （t = 7.704, 11.380, all P 〈 0.05）. The levels of TT3 [（373.32 ± 101.31） ng/L] and TT4 [（4.00 ±0.89） × 10^3 ng/L] in serum of hypothyroidism group were found to be significantly decreased, whereas the level of TSH [（5.77 ± 0.89） × 10^3 U/L] was increased in comparison with those of the control groups [（1 000.01 ± 273.53） ng/L, （44.33 ±7.84） × 10^3 ng/L, （1.87 ± 0.70） × 10^3 U/L, t = 5.262, 12.520, 8.413, all P 〈 0.05]. Compared with control group （1.00 ± 0.08, 1.01 ± 0.04）, the c-fos and c-jun mRNA expression （0.67 ± 0.03, 0.75 ± 0.02） of hypothyroidism group was significant decreased （t = 12.382, 13.784, all P 〈 0.05）. Conclusion Hypothyroidism may reduce mRNA expression levels of testicular c-fos and c-jun, and then damage the reproductive system in male rats.