Pharmacological studies on cefoperazone tylosin and their interaction in laboratory animals

The present study was conducted to explore the pharmacodynamiceffects of cefoperazone and tylosin and their combinations on rabbit’sdifferent tissues, blood picture, liver and kidney functions.The obtained results are summarized as follows.Effects on isolated smooth muscles:A dose dependent inhibitory effect was produced by cefoperazone,tylosin and their combination on the duodenum, uterus and trachea ofrabbits. These effects were attributed to a direct effect of the drugs onthe smooth muscles cell membrane.A relaxant effects were achieved by cefoperazone, tylosin and theircombination on the rabbit aortic strip preparations which might be of adirect effect on vascular smooth muscles cell membrane.Effects on the neuromuscular junction:Neither cefoperazone nor tylosin had effect on the directly andindirectly stimulated rabbit diaphragmatic muscles . Even though ,combination of both drugs had no effects on the skeletal muscles.