An inhibitor of poly(adenosine 5'-diphosphoribose) synthetase, 3-aminobenzamide, does not improve cardiovascular depression, bronchospasm, or survival associated with systemic anaphylaxis in rabbits in vivo.

: We investigated whether an inhibitor of poly(adenosine 5'-diphosphoribose) synthetase (PARS) is beneficial in anaphylaxis. Twenty-eight rabbits were randomly allocated to three groups: Group I (control) received .9% NaCl solution 10 min before antigen challenge followed by the infusion of the same solution. Group II (3-aminobenzamide 20 mg.kg-1) received 20 mg.kg-1 of 3-aminobenzamide (a PARS inhibitor) 10 min before antigen challenge followed by the continuous infusion of 20 mg.kg-1 of 3-aminobenzamide. Group III received 40 mg.kg-1 10 min before antigen challenge followed by the continuous infusion of 20 mg.kg-1 of 3-aminobenzamide. Survival were similar between three groups. Heart rate, mean arterial pressure (MAP), central various pressure, and pulmonary resistance did not differ between three groups. Dynamic pulmonary compliance did not differ in the early phase after the antigen challenge; however, it was significantly lower in Group III than in Groups I and II 15 min after the initiation of anaphylaxis. 3-aminobenzamide per se did not affect heart rate, MAP, central venous pressure, pulmonary resistance, or dynamic pulmonary compliance in animals without systemic anaphylaxis. In conclusion, this PARS inhibitor did not improve cardiovascular depression or bronchospasm in the early phase of systemic aggregated anaphylaxis in rabbits in vivo, implying that the pathophysiological changes associated with systemic anaphylaxis may not be related to activation of an energy-consuming DNA repair cycle triggered by PARS.