Ozkan Yusuf, Dönder Emir, Güney Hasan, Baydaş Giyaseddin
Firat University School of Medicine, Department of Endocrinology, Elazig, Turkey.
Neuro Endocrinol Lett. 2005 Oct;26(5):536-40.
It is claimed in a limited number of studies carried out on human beings that plasma homocysteine levels increased in hypothyroid patients and decreased in hyperthyroid patients.
The aim of this study is to determine total plasma homocysteine, thyroid function tests, vitamin B12, folic acid and lipid levels and to explore the relations among them in rat models with induced hypothyroidism and hyperthyroidism with a view to investigating whether hypothyroid and hyperthyroid rat models could represent human hypothyroidism and hyperthyroidism models.
The study included 30 male Wistar Albino species rats with a mean weight of 200 - 250 g. Rats were randomly divided into 3 groups as 1) hypothyroid group, 2) hyperthyroid group and 3) control group. Hypothyroidism was induced by adding 10 mg/kg/day propylthiouracil to rats' drinking water for 30 days. In order to induce hyperthyroidism, rats were administered 10 microg/100 g L-thyroxin ampule via intraperitoneal route for 10 days.
We found that total plasma homocysteine level of the hypothyroid group was significantly lower than those of the control group (p<0.05) and the hyperthyroid group (p<0.001). Total plasma homocysteine level of the hypothyroid group was found insignificantly higher than that of the control group (p>0.05) and significantly higher than that of the hyperthyroid group (p<0.001). We established a significant and positive correlation between total plasma homocysteine level and thyroid hormone levels. We did not identify a significant relation between total plasma homocysteine level and serum folic acid and serum vitamin B12 levels.
Our findings are different from the findings reported in human hypothyroidism and hyperthyroidism studies. We believe that hypothyroid and hyperthyroid rat models cannot represent human hypothyroidism and hyperthyroidism models.
在少数针对人类开展的研究中称，甲状腺功能减退患者的血浆同型半胱氨酸水平升高，而甲状腺功能亢进患者的该水平降低。
本研究旨在测定甲状腺功能减退和甲状腺功能亢进大鼠模型的血浆总同型半胱氨酸、甲状腺功能检查、维生素B12、叶酸和血脂水平，并探讨它们之间的关系，以研究甲状腺功能减退和亢进大鼠模型是否能代表人类甲状腺功能减退和亢进模型。
本研究纳入30只平均体重为200 - 250 g的雄性Wistar白化大鼠。大鼠被随机分为3组：1）甲状腺功能减退组，2）甲状腺功能亢进组，3）对照组。通过在大鼠饮用水中添加10 mg/kg/天的丙硫氧嘧啶30天来诱导甲状腺功能减退。为诱导甲状腺功能亢进症，通过腹腔注射途径给大鼠注射10 μg/100 g的L-甲状腺素安瓿，持续10天。
我们发现，甲状腺功能减退组血浆总同型半胱氨酸水平显著低于对照组（p<0.05）和甲状腺功能亢进组（p<0.001）。甲状腺功能减退组血浆总同型半胱氨酸水平虽高于对照组，但差异不显著（p>0.05），且显著高于甲状腺功能亢进组（p<0.001）。我们发现血浆总同型半胱氨酸水平与甲状腺激素水平之间存在显著正相关。我们未发现血浆总同型半胱氨酸水平与血清叶酸和血清维生素B12水平之间存在显著关系。
我们的研究结果与人类甲状腺功能减退和亢进研究报告的结果不同。我们认为甲状腺功能减退和亢进大鼠模型不能代表人类甲状腺功能减退和亢进模型。
