Observations on Anaphylactic and Compound 48/80‐Induced Histamine Release from Guinea‐Pig and Rat Lung Tissue in Vitro

The effect of oxygen lack on anaphylactic histamine release from sensitized guinea‐pig and rat lung tissue in vitro has been investigated, and found to consist of pronounced inhibition, provided that the incubation medium (phosphate buffer) was devoid of glucose. In the presence of glucose, this inhibition was overcome progressively with rising concentrations of glucose. Under oxygen, the anaphylactic histamine release from guinea‐pig lung tissue was also enhanced by the presence of glucose. By comparing anaphylactic histamine release from guinea‐pig lung tissue and Compound 48/80‐induced histamine release from rat lung tissue in glucose‐containing phosphate buffer and Tyrode solution, respectively, it has been demonstrated that pH changes produced by gassing the Tyrode solution with oxygen and nitrogen have obscured the true effect of nitrogenation in earlier investigations performed in glucose‐containing Tyrode solution.