The use of okadaic acid in vivo and the induction of molecular changes typical for Alzheimer's disease
The use of okadaic acid in vivo and the induction of molecular changes typical for Alzheimer's disease
复制标题
DOI：
10.1016/s0306-4522(97)00697-0
复制
发表时间：
1998-08-01
期刊：
影响因子：
3.3
通讯作者：
Gärtner, U
中科院分区：
文献类型：
--
作者：
Arendt, T;Holzer, M;Gärtner, U
将 OA (1 gg) 注射到大鼠大脑皮层，用 mab AT8 和 tau-1 检测 tau 的磷酸化状态。通过酶联免疫吸附测定对从注射部位新鲜解剖的 50 mg 脑组织的热稳定蛋白部分进行免疫反应性评估。三只动物的平均值：t：SEM 一些磷酸表位到死后去磷酸化，这需要对组织进行仔细且非常快速的处理。 6 例如，广泛用于检测 tau 的 PHF 样磷酸化的 AT8 表位对人脑和大鼠脑中的死后去磷酸化特别敏感。 o当我们开始单点急性注射 OA 的实验时，我们很快意识到，根据磷酸化位点，这些动物中诱导的 tau 磷酸化状态在数小时和数天内是可逆的。 2" 4" 16 例如，mab AT8 检测到的磷酸化增加在 12 至 24 小时内恢复到对照水平，而 tau-1 表位的变化持续超过一天（图 1）。这可能另外解释了为什么 OA 治疗后 tau 的过度磷酸化可以更容易地用 tau-1 比 AT8 检测到。~ 4 由于 tau 磷酸化的可逆性，急性注射 OA 似乎不适合诱导病理事件，例如 PHF 形成，这一过程在 AD 大脑中可能需要数十年的时间。可能有两种方法可以克服这个缺点。要么通过给予更高剂量来延长 OA 的作用，要么长期使用。我们选择了后者，因为 OA 无疑具有高度细胞毒性，这明显限制了剂量的增加。
injection of OA (1 gg) into rat cerebral cortex on the phosphorylation state of tau detected with the mab AT8 and tau-1. Immunoreactivity was assessed by enzyme-linked immunosorbent assay in heat-stable protein fraction of 50 mg brain tissue freshly dissected from the injection site. Mean values of three animals: t: SEM some phospho-epitopes to post mortem dephosphorylation which requires a careful and very rapid processing of the tissue. 6 The AT8 epitope, for example, that is widely used to detect a PHF-like phosphorylation of tau is particularly sensitive to post mortem dephosphorylation both in human] 9 and rat brain. oWhen we started the experiments with single-sited acute injections of OA, we soon realized that the induced phosphorylation state of tau in these animals is reversible within hours and days depending on the phosphorylation site. 2" 4" 16 The increase in phosphorylation detected by the mab AT8, for example, returns to control levels within 12 to 24h, while changes in the tau-1 epitope persist for more than one day (Fig. 1). This might additionally explain why hyperphosphorylation of tau after OA treatment can more easily be detected with tau-1 than with AT8.~ 4 Because of this reversibility of tau-phosphorylation, the acute injection of OA did not appear to be suitable to induce pathological events such as PHF-formation, a process that in the AD brain might take decades. Potentially, there are two ways to overcome this drawback. Either to prolong the action of OA by giving a higher dose, or to apply it chronically. We have chosen the latter, because OA beyond doubt is highly cytotoxic which clearly limits an increase of the dosage.