Smooth muscle response in anaphylaxis. I. Effect of mixtures of antigen and sensitized lung tissues.

Abstract

Anaphylaxis, according to present conception, is essentially a cellular phenomenon. Of the tissues that are known to participate in anaphylactic shock, that of smooth muscle has received most attention. It has been shown both in the living sensitized animal 1 and also in vitro by the Dale experiment 2 that when certain organs containing smooth muscle are exposed to the antigenic substance to which the animal is sensitized, this smooth muscle responds by contraction. Such smooth muscle contraction is responsible for many anaphylactic symptoms. In guinea pigs, with which these experiments are concerned, anaphylactic death is due primarily to the contraction of the highly developed smooth musculature of the bronchioles with subsequent asphyxia. As this may be entirely a peripheral reaction, as Auer 3 has shown, the injected antigen presumably is transported by the blood to the lungs where it finds receptive smooth muscle. Essentially nothing is known, however, about the stimulus which makes smooth muscle contract under these conditions. By utilizing this lung reaction, experiments were attempted to study this problem and the first of these is reported here.

Female virgin guinea pigs of about 250 grams were injected intraperitoneally with 0.1 cc. of egg-white solution with an average nitrogen content of 2.6 mg. per cc.; other lots received 0.5 cc. of horse epithelium extract with a nitrogen content of 0.6 mg. per cc. Both of these were shown to be anaphylactogenic. About twenty-one days later, when optimum sensitivity developed, the animals were killed by fracturing the skull. In each, the uterus was perfused with warm Tyrode solution until free from visible blood. The two anterior uterine horns were then suspended, each in a separate Dale apparatus in which a bath of 250 cc. of Tyrode solution was used.