Changes in Antitryptic Power of the Blood Associated with Anaphylaxis in Guinea Pigs

Abstract

That the natural antitrypsin of body fluids plays a determining role in anaphylaetic reactions was postulated many years ago, 1 , 2 , 3 but the theory has since been almost totally neglected, probably because of the lack of a simple reliable quantitative test for antitrypsin. The present paper records preliminary results of a study in which changes in serum antitrypsin associated with guinea pig anaphylaxis were determined by a new procedure developed by the writer. 4

Methods and Materials. From a group of 30 male guinea pigs sensitized to egg white blood samples were taken aseptically by heart puncture, without anesthesia, during the incubation period, just before and just after introduction of the shocking dose of the antigen, at death, and, in the case of surviving animals, at various intervals of time after the antigen injections. Normal guinea pigs, inoculated intracardially with egg white as controls, were similarly bled. Blood specimens before and immediately after intracardial antigen injections were obtained in the following way: (1) heart was punctured and the first sample was drawn into the syringe, which was then detached, leaving the needle in the heart, (2) a second syringe containing egg white was connected to the needle and the shocking dose was injected, (3) this syringe was now removed and replaced by a third syringe into which was drawn at once the second sample of blood. Sera collected from the clotted blood specimens were centrifuged until perfectly clear and stored in the refrigerator in sealed sterile tubes until tested.

The antitryptic power of these sera was determined by the film-disc method, following a procedure much simplified and improved over that originally described. 5 Photographic film which has been exposed, developed and hardened in a particular manner is cut into discs 5 mm in diameter.