Department of Physiology, Ribeirão Preto School of Medicine, University of São Paulo, Ribeirão Preto, SP, CEP 14049-900, Brazil.
Brain Res. 2011 Mar 24;1381:141-7. doi: 10.1016/j.brainres.2011.01.042. Epub 2011 Jan 21.
The Wistar Audiogenic Rat (WAR) strain is a genetic model of sound-induced reflex epilepsy which was selected starting from audiogenic seizures susceptible Wistar rats. Wistar resistant rats were used as WAR's control in this study. In the acute situation, audiogenic seizures (AS) in WARs mimic tonic-clonic seizures and, in the chronic protocol, mimic temporal lobe epilepsy. AS have been shown to evoke neuroendocrine responses; however, the hypothalamic-pituitary-adrenal activity in the WAR has not been established. The aim of this study was to evaluate the hypothalamic-pituitary-adrenal axis (HPA) responses to exogenous ACTH stimulation (8 ng/rat), fifteen minute restraint stress and circadian variation (8 am and 8 pm) under rest conditions in these animals through plasma measurements of ACTH and corticosterone concentrations. We also measured the body weight from birth to the 9th week of life and determined adrenal gland weight. We found that WARs are smaller than Wistar and presented a higher adrenal gland weight with a higher level of corticosterone release after intravenous ACTH injection. They also showed altered HPA axis circadian rhythms and responses to restraint stress. Our data indicate that, despite the lower body weight, WARs have increased adrenal gland weight associated with enhanced pituitary and adrenal responsiveness after HPA axis stimulation. Thus, we propose WARs as a model to study stress-epilepsy interactions and epilepsy-neuropsychiatry comorbidities.
Wistar 听觉诱发癫痫大鼠（WAR）品系是一种声音诱导反射性癫痫的遗传模型，它是从易患听觉性癫痫发作的 Wistar 大鼠中选择出来的。在这项研究中，Wistar 抗性大鼠被用作 WAR 的对照。在急性情况下，WAR 中的听觉性癫痫（AS）模拟强直阵挛性癫痫发作，而在慢性方案中，模拟颞叶癫痫发作。已经证明 AS 会引起神经内分泌反应；然而，WAR 中的下丘脑-垂体-肾上腺（HPA）活动尚未确定。本研究旨在通过测量 ACTH 和皮质酮浓度来评估这些动物在应激状态下对外源性 ACTH 刺激（8ng/大鼠）、15 分钟束缚应激和昼夜节律（8 点和 8 点）的下丘脑-垂体-肾上腺轴（HPA）反应在 rest 条件下。我们还测量了从出生到第 9 周的体重，并确定了肾上腺重量。我们发现，WAR 比 Wistar 小，并且在静脉注射 ACTH 后，肾上腺重量更高，皮质酮释放水平更高。它们还显示出 HPA 轴昼夜节律和对束缚应激的反应发生改变。我们的数据表明，尽管体重较低，但 WAR 具有更高的肾上腺重量，并且在 HPA 轴刺激后垂体和肾上腺的反应性增强。因此，我们提出 WAR 作为研究应激-癫痫相互作用和癫痫-神经精神病共病的模型。
