Role of transmembrane ion currents in the mechanism of action of beta-adrenoblockers
Porotikov, V.I.; Cherenshchikova, E.A.; Filippov, A.K.; Mashkovskiĭ, M.D.; Iuzhakov, S.D.
Biulleten' Eksperimental'noi Biologii i Meditsiny 97(6): 677-679
1984
ISSN/ISBN: 0365-9615 PMID: 6146358 Document Number: 233469
The effects of propranolol, oxprenolol, pindolol, labetalol, and atenolol on the isoproterenol-stimulated slow calcium current as well as on spontaneous slow calcium and fast sodium currents were studied in frog trabeculae by the double sucrose bridge technique. Administration of beta-adrenoblockers in low doses (10(-7)-10(-6)M) antagonized the stimulatory effect of isoproterenol on the slow calcium current (pindolol greater than oxprenolol greater than or equal to propranolol = labetalol greater than atenolol). When administered in high doses (2 X 10(-6)-10(-4)M) the beta-adrenoblockers reduced the slow calcium current. Meanwhile, some of them (propranolol, oxprenolol, labetalol) suppressed the fast sodium current.