Source: Liao, S. et. al. Direct Intrabronchial Administration to Improve the Selective Agent Deposition Within the Mouse Lung. J. Vis. Exp. (2019).
This video describes an intrabronchial approach to administer an experimental agent selectively into distal right and left lung. In the featured protocol, we will administer bleomycin intrabronchially into a mouse to obtain a better model for pulmonary fibrosis.
All procedures involving animals have been reviewed by the local institutional animal care committee and the JoVE veterinary review board.
1. Non-operative IB intubation and delivery approaches
Figure 1: Approach for selective right/left lung lobar cannulation and administration. (A) To target the right lung, the plastic board is rotated +30°, improving ease of selectively engaging the right mainstem bronchus. The catheter is advanced (per distances proposed in Table 1) to selectively engage right sided lobes. 20 µL of 0.3% EBD was administered. In ~90% of attempts, the posterior lobe is cannulated. The remaining 10% of attempts engage the inferior lobe. (B) To target the left lung, the plastic board is first rotated -74° for left mainstem engagement. After successful intubation of the catheter, rotation is then decreased to -30° to allow for gravity to assist with agent delivery. To prove selective engagement of the left side, 40 µL of 0.3% EBD was delivered. This approach consistently (100% of attempts) targeted left lung basilar segments.
Body weight (g) | Number of mice tested | Catheter depth (mm) for Selective cannulation |
Catheter depth (mm) for whole lung cannulation | |
Right lung | Left lung | |||
15 – 19 | 17 | 37 | 38 | 26 |
20 – 25 | 22 | 38 | 39 | 27 |
25 – 30 | 29 | 39 | 40 | 28 |
> 30 | 11 | 40 | 41 | 31 |
Table 1: Suggested depth of catheter insertion. Predicted catheter depths necessary to selectively cannulate the distal and proximal lungs were empirically determined using C57BL/6 mice of various weights (total = 79 mice).
The authors have nothing to disclose.
22 G shielded IV Catheter | BD | 381423 | |
Evans blue dye | Sigma-Aldrich | E2129 | |
LED-30W Fiber Optic Dual Gooseneck Lights Microscope Illuminator | AmScope | LED-30W | |
Precisionglide needle, 18G x 1" | BD | 305195 | Beveled tip, 12 mm in length |