Myocardial damage during protracted anaphylactic shock in guinea pigs

In ovalbumin-sensitized, mepyramine-treated guinea pigs protracted anaphylactic shock was elicited by i.v. injection of antigen. Diffuse or focal necrosis of myocardial cells was found in animals which died in protracted shock, as well as perivascular and interstitial edema. The antigen effects could be partially imitated by i.v. infusion of high amounts of adrenaline into nonsensitized guinea pigs. When adrenaline was infused during protracted anaphylactic shock, the catecholamine effects did not add to the histological effects of the antigen. Rather, the morphological alterations in the hearts were reduced, whereas the survival times were not increased, but decreased. - The findings are discussed in view of the nature of protracted anaphylactic shock.