Manaenko Anatol, Lekic Tim, Zhang John H, Tang Jiping
Department of Physiology and Pharmacology, Loma Linda University, Loma Linda, CA 92354, USA.
Acta Neurochir Suppl. 2011;111:155-9. doi: 10.1007/978-3-7091-0693-8_26.
There is mounting evidence suggesting that arginine vasopressin via its V1a receptor interaction is involved in the regulation of the brain water channel, aquaporin-4 (AQP4). The role of AQP4 in brain edema resolution has been thoroughly investigated in knock-out animal studies, which showed that its depletion increases brain water content in models of vasogenic edema. As a result, we tested the hypothesis that the activation of V1a receptor by it selective agonist will decrease brain edema in a mouse intracerebral hemorrhage (ICH) model.
ICH was induced by injection of bacterial collagenase into the right basal ganglia in CD1 male mice (weight 30-35 g). The animals were divided into the following groups: sham, ICH+vehicle, and ICH+AVP V1a receptor agonist. Brain edema and neurological outcomes were evaluated at 24 and 72 h post-ICH.
We found that collagenase injection increased brain edema and resulted in subsequent neurobehavioral deficits at both time points. Treatment with our agonist had no effect on the ICH outcomes at both time points.
Our results suggest that the activation of the V1a receptor has no beneficial effect on secondary brain injury following ICH in mice.
越来越多的证据表明,精氨酸加压素通过其与V1a受体的相互作用参与脑水通道蛋白4(AQP4)的调节。在基因敲除动物研究中,对AQP4在脑水肿消退中的作用进行了深入研究,结果表明,在血管源性脑水肿模型中,AQP4的缺失会增加脑含水量。因此,我们检验了以下假设:在小鼠脑出血(ICH)模型中,其选择性激动剂激活V1a受体将减轻脑水肿。
通过向CD1雄性小鼠(体重30 - 35 g)右侧基底节注射细菌胶原酶诱导ICH。将动物分为以下几组:假手术组、ICH + 赋形剂组和ICH + AVP V1a受体激动剂组。在ICH后24小时和72小时评估脑水肿和神经功能结局。
我们发现注射胶原酶会增加脑水肿,并在两个时间点导致随后的神经行为缺陷。在两个时间点,用我们的激动剂治疗对ICH结局均无影响。
我们的结果表明,激活V1a受体对小鼠ICH后的继发性脑损伤没有有益作用。