A method for intratracheal instillation of endotoxin into the lungs of mice.

A detailed method is presented for the intratracheal instillation of fluids into the lungs of mice. Using 125I-albumen it was determined that 25-50 microliters of volume gave almost equal distribution to all lobes of the mouse lung. Extremely low levels of endotoxin given intratracheally (12.5-25 ng) resulted in a dramatic increase in the neutrophil content of the lung. The increase started in less than 4 h, reaching levels of 7 x 10(5) by 18 h and was maintained at elevated levels for at least 48 h. This neutrophil count represented more than 90% of the cell population of the lung.