Acute and Chronic Inflammatory Responses to Contrast Agent Aspiration and their Mechanisms in the Rat Lung

Objectives: Contrast agent (CA) aspiration is an established complication of upper gastrointestinal and videofluoroscopic swallow studies. The underlying molecular biological mechanisms of acute response to CA aspiration in the respiratory organs remain unclear. The aims of this study were to elucidate the histological and biological influences of three kinds of CA on the lung and to clarify the differences between acute and chronic responses. Methods: Eight-week-old male Sprague Dawley rats were divided into 5 groups (n=6 per group). Three groups underwent tracheal instillation of one of three CAs: barium sulfate (Ba), ionic iodinated contrast agent (ICA), and non-ionic iodinated contrast agent (NICA). Sham and control groups were instilled with air and saline. Animals were euthanized 2 days (acute response) and 30 days (chronic response) after treatment, and histological and gene analyses 日本音声言語医学会平成 30 年度(第 12 回)音声言語医学に関する研究助成成果報告論文 東京大学耳鼻咽喉科・頭頸部外科:〒113-8655 東京都文京区本郷 7-3-1 CRC 2F Department of Otolaryngology, The University of Tokyo: 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8655, Japan 2019 年 5 月 15 日受稿 2019 年 6 月 17 日受理