Canine Model Investigating Cardiopulmonary Effects B. anthracis Edema and Lethal

在本研究中，已经开发了犬模型来研究ETx和LeTx单独和一起的心肺效应。该模型使用持续镇静和机械通气的动物，其具有适当的全身和肺动脉导管。血管内血流动力学研究由一系列超声心动图测量补充。在迄今为止的研究中，已经测试了作为24小时输注施用的单个毒素的效果。 在这些研究中，ETx和LeTx显示出产生非常不同的心血管损伤模式。ETx可显著降低早期出现的前负荷、心动过速和低血压，并持续长达96 h。另一方面，LeTx产生逐渐的低血压和左心室功能的进行性降低。因此，ETx似乎对外周血管系统具有深远的影响，而LeTx具有直接的心肌收缩效应。这些研究正在进行中，不久将评估这两种毒素的影响。迄今为止的发现强调了在炭疽相关休克期间直接针对这两种毒素的连续治疗是多么重要。

In the present study, a canine model has been developed to study the cardiopulmonary effects of ETx and LeTx alone and together. This model utilizes continuously sedated and mechanically ventilated animals that have both systemic and pulmonary arterial catheters in place. Intravascular hemodynamic studies are complemented by serial echocardiographic measures. In studies thus far, the effects of individual toxins administered as 24 h infusions have been tested. In these studies, ETx and LeTx have shown to produce very different patterns of cardiovascular injury. ETx produces marked decreases in preload, tachycardia and hypotension that occurs early and persists for up to 96 h. LeTx on the other hand produces gradual hypotension and progressive decreases in left ventricular function. Thus ETx appears to have profound effects on the peripheral vasculature while LeTx is having direct myocardial depressant effects. These studies are ongoing and will shortly assess the effects of the two toxins together. Findings to date emphasize how important adjunctive treatments may be that directly target the two toxins during anthrax associated shock.