Clinic of Nuclear Medicine, Jena University Hospital, Jena, Thuringia, Germany.
Translational Nuclear Medicine and Radiopharmacy, Clinic of Nuclear Medicine, Jena University Hospital, Jena, Thuringia, Germany.
Exp Biol Med (Maywood). 2024 May 24;249:10037. doi: 10.3389/ebm.2024.10037. eCollection 2024.
imaging using avian eggs has been described as a potential alternative to animal testing using rodents. However, imaging studies are hampered by embryonal motion producing artifacts. This study aims at systematically comparing isoflurane, desflurane and sevoflurane in three different concentrations in ostrich embryos. Biomagnetic signals of ostrich embryos were recorded analyzing cardiac action and motion. Ten groups comprising eight ostrich embryos each were investigated: Control, isoflurane (2%, 4%, and 6%), desflurane (6%, 12%, and 18%) and sevoflurane (3%, 5%, and 8%). Each ostrich egg was exposed to the same narcotic gas and concentration on development day (DD) 31 and 34. Narcotic gas exposure was upheld for 90 min and embryos were monitored for additional 75 min. Toxicity was evaluated by verifying embryo viability 24 h after the experiments. Initial heart rate of mean 148 beats/min (DD 31) and 136 beats/min (DD 34) decreased over time by 44-48 beats/minute. No significant differences were observed between groups. All narcotic gases led to distinct movement reduction after mean 8 min. Embryos exposed to desflurane 6% showed residual movements. Isoflurane 6% and sevoflurane 8% produced motion-free time intervals of mean 70 min after discontinuation of narcotic gas exposure. Only one embryo death occurred after narcotic gas exposure with desflurane 6%. This study shows that isoflurane, desflurane and sevoflurane are suitable for ostrich embryo immobilization, which is a prerequisite for motion-artifact free imaging. Application of isoflurane 6% and sevoflurane 8% is a) safe as no embryonal deaths occurred after exposure and b) effective as immobilization was observed for approx. 70 min after the end of narcotic gas exposure. These results should be interpreted with caution regarding transferability to other avian species as differences in embryo size and incubation duration exist.
使用禽类鸡蛋进行成像已被描述为替代使用啮齿动物进行动物测试的潜在方法。然而，成像研究受到胚胎运动产生伪影的阻碍。本研究旨在系统比较三种不同浓度的异氟烷、地氟烷和七氟烷在鸵鸟胚胎中的作用。通过分析心脏活动和运动来记录鸵鸟胚胎的生物磁信号。研究了由 8 个鸵鸟胚胎组成的 10 个组：对照组、异氟烷（2%、4%和 6%）、地氟烷（6%、12%和 18%）和七氟烷（3%、5%和 8%）。每个鸵鸟蛋在发育日（DD）31 日和 34 日暴露于相同的麻醉气体和浓度下。麻醉气体暴露持续 90 分钟，胚胎在额外的 75 分钟内被监测。实验结束后 24 小时验证胚胎活力来评估毒性。平均心率（DD31 日）为 148 次/分钟，（DD34 日）为 136 次/分钟，随着时间的推移降低了 44-48 次/分钟。组间无显著差异。所有麻醉气体在平均 8 分钟后均导致明显的运动减少。暴露于 6%地氟烷的胚胎显示残留运动。异氟烷 6%和七氟烷 8%在停止麻醉气体暴露后产生平均 70 分钟的无运动间隔。只有一只胚胎在暴露于 6%地氟烷后死亡。本研究表明，异氟烷、地氟烷和七氟烷适合鸵鸟胚胎固定，这是进行无运动伪影成像的前提。应用 6%地氟烷和 8%七氟烷 a）安全，因为暴露后没有胚胎死亡，b）有效，因为在麻醉气体暴露结束后约 70 分钟观察到固定。关于将这些结果转移到其他禽类物种，应谨慎解释，因为胚胎大小和孵化时间存在差异。
