Laboratorio de Ciencias Fisiológicas, Cátedra de Bacteriología y Virología Médicas, Facultad de Ciencias Médicas, Universidad Nacional de Córdoba, CP 5000 Córdoba, Argentina; Sección de Desarrollo Cerebral Perinatal (SPBD), Instituto de Histología y Embriología Mendoza (IHEM-CONICET), Facultad de Ciencias Médicas, Universidad Nacional de Cuyo, Parque General San Martín, CP 5500 Mendoza, Argentina.
Peptides. 2013 Nov;49:74-80. doi: 10.1016/j.peptides.2013.08.016. Epub 2013 Sep 9.
We previously showed that short-term hypo- and hyperthyroidism induce changes in neuropeptide glutamic-acid-isoleucine-amide (NEI) concentrations in discrete brain areas in male rats. To investigate the possible effects of hypo- and hyperthyroidism on NEI concentrations mainly in hypothalamic areas related to reproduction and behavior, female rats were sacrificed at different days of the estrous cycle. Circulating luteinizing hormone (LH), estradiol and progesterone concentrations were measured in control, hypothyroid (hypoT, treated with PTU during 7-9 days) and hyperthyroid (hyperT, l-T4 during 4-7 days) animals. Both treatments blunted the LH surge. Hypo- and hyperthyroidism increased estradiol concentrations during proestrus afternoon (P-PM), although hypoT rats showed lower values compared to control during proestrus morning (P-AM). Progesterone levels were higher in all groups at P-PM and in the hyperT during diestrus morning (D2). NEI concentrations were lower in hypoT rats during the estrous cycle except in estrus (E) in the peduncular part of the lateral hypothalamus (PLH). They were also reduced by both treatments in the perifornical part of the lateral hypothalamus (PeFLH) during P-PM. Hypothyroidism led to higher NEI concentrations during P-PM in the organum vasculosum of the lamina terminalis and anteroventral periventricular nucleus (OVLT+AVPV). The present results indicate that NEI concentration is regulated in a complex manner by hypo- and hyperthyroidism in the different areas studied, suggesting a correlation between NEI values and the variations of gonadal steroid levels during estrous cycle. These changes could be, in part, responsible for the alterations observed in the hypothalamic-pituitary-gonadal axis in these pathologies.
我们之前的研究表明，短期的甲状腺功能减退和甲状腺功能亢进会导致雄性大鼠不同脑区神经肽谷氨酸-异亮氨酸-酰胺（NEI）浓度发生变化。为了研究甲状腺功能减退和甲状腺功能亢进对与生殖和行为相关的下丘脑区域中 NEI 浓度的可能影响，我们在雌性大鼠的不同发情周期日处死它们。在对照组、甲状腺功能减退组（用 PTU 处理 7-9 天）和甲状腺功能亢进组（用 l-T4 处理 4-7 天）中测量循环促黄体生成素（LH）、雌二醇和孕酮浓度。这两种处理都削弱了 LH 峰。甲状腺功能减退和甲状腺功能亢进都会增加发情前期下午（P-PM）的雌二醇浓度，尽管甲状腺功能减退组在发情前期上午（P-AM）的浓度比对照组低。所有组在 P-PM 时孕酮水平较高，甲状腺功能亢进组在动情前期上午（D2）时孕酮水平也较高。除发情期（E）外，在发情周期的所有时期，甲状腺功能减退组大鼠的外侧下丘脑脚间核（PLH）的丘脑部的 NEI 浓度均较低。在发情前期下午（P-PM），两种处理也降低了外侧下丘脑室旁核（PeFLH）的 NEI 浓度。甲状腺功能减退症导致发情前期下午（P-PM）血管终板器官和前腹侧脑室下核（OVLT+AVPV）的 NEI 浓度升高。这些结果表明，NEI 浓度在不同研究区域受到甲状腺功能减退和甲状腺功能亢进的复杂调节，提示 NEI 值与发情周期中生殖类固醇水平的变化之间存在相关性。这些变化可能部分解释了这些病理状态下下丘脑-垂体-性腺轴的改变。
