[Morphometric study of the myocardial T-+L-system under the influence of the beta-adrenergic agent fenoterol].

In order to evaluate possible cardiotoxic properties of the beta adrenergic agent fenoterol, the effect of fenoterol alone and in combination with verapamil and prednisolone respectively was examined regarding the myocardial T- and L-system of 54 female rabbits. Five study groups and one control group measured the width morphometrically of the T- and L-system in electronmicroscopical pictures of the myocardium after treating the animals accordingly. A relevant dilatation of the T- and L-system was not found in this study, neither by morphological evaluation of the electron-microscopical pictures, nor in the morphometric-statistical analysis of the measurements in both experimental and control groups. Therefore, no pathological effects concerning the width of the T- and L-system could be found by applying fenoterol alone or in combination with the calcium antagonist verapamil and prednisolone respectively for tocolytic purposes.