Pharmacological Reactivity of an Isolated Tracheal Preparation of the Guinea-pig

Abstract

A method is described allowing a continuous record of the tonus in the isolated guinea-pig trachea. The pharmacological reactivity seems to be identical with that of other tracheal preparations. Acetylchollne, serotonine, histamine and BaCl2, constrict the trachea while sympathomimetics, theo-phylllne and papaverine dilate it. Anticholinergic, antihistaminlc and ganglion blocking drugs are mainly inactive. Pronethalol antagonizes the tracheodilatation produced by sympthomimetics, but not the theophylline - or papaverine-induced dilatation. A possible relation with the biochemical hypothesis of Sutherland and Rail is mentioned.