Anaphylactoid Response in Guinea Pigs to the Parenteral Administration of Sulphate Esters of High Molecular Weight of Dextran

Abstract

DURING an investigation of the biological activity of the synthetic heparinoid anticoagulant, dextran sulphate, it was noted that the parenteral administration of certain samples gave rise to a peculiar transitory reaction in guinea pigs¹. This reaction was anaphylactoid in type, being characterized by jactitating convulsions followed by acute circulatory collapse. Although superficially resembling true anaphylaxis, it differed from the latter in that (a) it occurred in animals which had not been exposed previously to dextran sulphate ; (b) it was not accompanied by severe respiratory embarrassment. No coughing, wheezing or sneezing occurred, and animals killed during attacks showed no evidence of bronchiolar constriction or pulmonary emphysema ; (c) the reaction could not be prevented or inhibited by large doses of the antihistamine compounds which inhibit anaphylaxis². Equivalent doses of the compounds producing this effect in the guinea pig did not produce similar reactions in the mouse, rat, rabbit, dog or baboon.