Open AccessThe Effect of Nipradilol on the Isoproterenol-Induced Depression of Contractions in the Cat Soleus Muscle.
Author(s) -
Toshihiko Tanaka,
Naoki Murata,
Yoichi Yamauchi
Publication year - 1999
Publication title -
japanese journal of pharmacology/japanese journal of pharmacology
Language(s) - English
Resource type - Journals
eISSN - 1347-3506
pISSN - 0021-5198
DOI - 10.1254/jjp.81.286
Subject(s) - propranolol , chemistry , cats , medicine , soleus muscle , muscle contraction , endocrinology , skeletal muscle
The effect of nipradilol on the isoproterelol-induced depression of contractions of the soleus muscle of the anesthetized cats was studied. Isoproterenol (0.3 microg/kg) injected intravenously decreased the tension and degree of fusion of incomplete tetanic contractions of the soleus muscle of the anesthetized cats. The effect of isoproterenol was blocked by nipradilol (> or = 3 microg/kg), desnitro-nipradilol (> or = 10 microg/kg) and propranolol (> or = 10 microg/kg), but not by nitroglycerin (10-100 microg/kg). Nipradilol (30 microg/kg) and desnitronipradilol (300 microg/kg) almost completely antagonized the depressor effects of isoproterenol. These results coupled with evidence that nipradilol does not penetrate the blood-brain barrier indicate that nipradilol exerts an anti-tremor action by blocking peripheral beta2-adrenoceptors.