背景:高剂量率放疗在保存正常组织方面显示出有希望的结果。我们开发了一个离体模型来研究实验性放射治疗在啮齿动物食管平滑肌中的生理作用。
方法:我们评估了食管功能的生理参数,中间,和器官浴中的远端部分。使用峰值剂量大于200Gy的微束辐照(MBI)技术和剂量在3.5-4Gy之间的宽束辐照(BBI)进行高剂量率同步加速器辐照。
结果:MBI和BBI均不影响收缩器的功能。虽然BBI组的峰值潜伏期和最大力变化不受影响,MBI后食管近端段没有变化,在食管中段和远端段观察到峰值潜伏期的显著增加和最大力变化的减少.
结论:在我们的模型中,高剂量率放疗后食管收缩的生理参数没有严重变化,但我们的结果显示食管功能延迟.从临床的角度来看,观察到的峰值潜伏期增加和最大力变化减少可能表明食管转运延迟。
High-dose-rate radiotherapy has shown promising results with respect to normal tissue preservation. We developed an ex vivo model to study the physiological effects of experimental radiotherapy in the rodent esophageal smooth muscle.
We assessed the physiological parameters of the esophageal function in ex vivo preparations of the proximal, middle, and distal segments in the organ bath. High-dose-rate synchrotron irradiation was conducted using both the microbeam irradiation (MBI) technique with peak doses greater than 200 Gy and broadbeam irradiation (BBI) with doses ranging between 3.5-4 Gy.
Neither MBI nor BBI affected the function of the contractile apparatus. While peak latency and maximal force change were not affected in the BBI group, and no changes were seen in the proximal esophagus segments after MBI, a significant increase in peak latency and a decrease in maximal force change was observed in the middle and distal esophageal segments.
No severe changes in physiological parameters of esophageal contraction were determined after high-dose-rate radiotherapy in our model, but our results indicate a delayed esophageal function. From the clinical perspective, the observed increase in peak latency and decreased maximal force change may indicate delayed esophageal transit.