Isoflurane anesthetized mice were suspended on an inclined table with a V-shaped notch, into which the mouse head was placed. The mouse was fixed with a thread for the upper incisors so that the entrance to the oral cavity was opened. In this position - with the head thrown back up - the epiglottis completely blocks the entrance to the esophagus. This ensures that the entire volume of fluid flows directly into the trachea.
After that, with the help of a flashlight, bleomycin solution (30 mkg) drop by drop was pipetted onto the glottis. Inhalation of liquid was monitored, firstly, visually, and secondly, by the remarkable sound in the lungs.
In case of labored or suppressed breathing, the mice were stimulated by massaging the chest with two fingers.
The whole procedure continued no longer than 60 sec and ended before the mouse woke up. No animals died as a result of the administration procedure.
All manipulations with animals are approved by the Moscow State University bioethics committee.
