EFFECT OF GUINEA-PIG PURIFIED IMMUNOGLOBULIN G1 ON THE RESPONSIVENESSOF TRACHEAL, AORTIC, VAS-DEFERENS AND ILEUM SMOOTH MUSCLES

Background Smooth muscles hyperresponsiveness is a common feature in a naphylaxis and allergic diseases. Objective The aim of the present wor k was to investigate the effect of in vitro passive sensitization with highly purified immunoglobulin G1 (IgG1) on the responsiveness of tra cheal, aortic, vas deferens and ileum smooth muscles. Methods Firstly, IgG1, obtained from actively sensitized BFA guinea-pigs, was purified by Protein A-Sepharose column and characterized by enzyme-linked immu nosorbent assay (ELISA) and immunoelectrophoresis analysis. Concentrat ion-response curves to spasmogens (acetylcholine for trachea and vas d eferens, noradrenaline for aorta and histamine for ileum) were establi shed before and after in vitro passive sensitization with IgG1. Result s Contractile responses and maximal contractions were significantly en hanced after passive sensitization for all the organs. Maximal contrac tions were significantly increased in the trachea (+ 46.7%), aorta (51%), vas deferens (+ 114.2%) and ileum (+ 117.2%). At the end of the experiments, the application of the sensitizing antigen induced a sign ificant Schultz-Dale reaction of the smooth muscles. Conclusion The pr esent results show that the in vitro application of purified IgG1 can produce non-specific smooth muscle hyperreactivity and hypersensitivit y. So, IgG1 can be considered as the main factor involved in the genes is of sensitization-induced hyperresponsiveness, and probably play a g reat role in hyperreactivity observed during allergic diseases and ana phylaxis.