Inhibition of protein exudation from the trachea by corticotropin-releasing factor

Increased vascular permeability in the trachea, as measured by Evans blue dye leakage, was produced in the anesthetized rat by antidromic stimulation of the right vagus or by exposure to dilute formalin vapors. Corticotropin-releasing factor (CRF) inhibited tracheal protein extravasation at dosages of 6-24 nmol (29-114 micrograms)/kg i.v. injected 10 min before nerve stimulation or formaldehyde exposure. The decrease in respiration rate and blood pressure produced by formaldehyde was also attenuated by CRF.