Effect of Cortisone on Histamine Liberation Induced by Tween in the Dog.

Abstract
The injn. of Tween 20 in the dog is followed by the appearance of histamine in the plasma, as demonstrated by paper chromatography. Cortisone does not prevent the hypotensive effect of the 1st injn. of Tween 20, in the male dog. Cortisone prevents or decreases the hypertensive effect of a 2d injn. of Tween 20 administered 24 or 48 hrs. after the 1st injn. Cortisone does not prevent the hypotensive effect of injected histamine. It is postulated that cortisone prevents the accumulation of histamine in the tissues following the release of this compound by Tween 20.