%R MTMT:1132529
%O MegjegyzĂŠs-20433862
SU: Suppl. 1
MegjegyzĂŠs-20434441
SU: Suppl. 1
Cited By :31            
            Export Date: 4 October 2019            
            Correspondence Address: Papp, J.G.; Albert Szent-GyĂśrgyi Medical University, Department of Pharmacology, DĂłm tĂŠr 12 POB 15, Szeged, H-6701, Hungary            
            Chemicals/CAS: Calcium, 7440-70-2; Cardiotonic Agents            
            Tradenames: arikin z; bay k 8644; dpi 201 106; emd 53998; opc 8212
%L publicatio32582
%D 1995
%V 26
%X A number of new positive inotropic agents with diverse mechanisms of
action have been discovered over the past 20 years. Most of these
cardiotonic drugs exhibit characteristic electrophysiologic profiles.
This prompted us to propose a classification scheme based on
electrophysiologic principles, modifying the categories recently
suggested by another author. Class I actions designate positive
inotropic mechanisms that enhance the transmembrane calcium current by
various means, such as beta-receptor stimulation (dobutamine, class
I/A), phosphodiesterase inhibition (milrinone, class I/B), direct
stimulation of adenylate cyclase (forskolin, class I/C), or direct
modulation of calcium channel gating (BAY K 8644, class I/D). Class II
action includes mechanisms that lead to elevation of intracellular
sodium activity either by inhibiting the Na,K pump (digitalis, class
II/A) or by increasing transmembrane sodium influx (DPI 201-106, class
II/B). Class III action involves a mechanism by which sensitivity of
the myofilaments to calcium increases (EMD 53998, levosimendan). This
mechanism is not associated with apparent electrophysiologic
manifestations. Positive inotropism due to lengthening of the cardiac
repolarization (almokalant) is considered as class IV action. The
possible clinical implications of the various positive inotropic
mechanisms are also discussed.
%J JOURNAL OF CARDIOVASCULAR PHARMACOLOGY
%I szgyaoe
%P S32-S44
%A  VarrĂł AndrĂĄs
%A  Papp Gyula
%T Classification of positive inotropic actions based on electrophysiologic characteristics: Where should calcium sensitizers be placed?
%N Suppl. 1