Electrophysiology of Dihydropyridine Calcium Agonists

  • M. Bechem
  • M. Schramm
Part of the Bayer AG Centenary Symposium book series (BAYER)


In recent years reports have been published on five structurally different 1,4-dihydropyridine (DHP) calcium agonists, the chemical structures of which are shown in Fig. 1 (for review see [14]. Each has an asymmetric carbon atom in position 4 of the dihydropyridine ring, resulting in the existence of two enantiomers for each compound. For 202-791, H160/51 and Bay K8644 the enantiomers have been separated; calcium agonism was found to be associated with only one enantiomer, while calcium antagonism was displayed by the other. Fortunately, for the best investigated calcium agonist - Bay K8644 - the potency of the calcium-antagonistic (+ )-R-enantiomer is much lower than that of the calcium-agonistic (-)-S-enantiomer [4]. Therefore, results obtained from investigations with racemic Bay K8644 can be considered as effects of a “pure” calcium agonist. Estimated from the pharmacological profile, the same seems to be true for CGP 28–392, although this has not been proven.


Atrial Myocytes Negative Membrane Potential Asymmetric Carbon Atom Dihydropyridine Ring Patch Clamp Pipette 
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Copyright information

© Springer-Verlag Berlin Heidelberg 1988

Authors and Affiliations

  • M. Bechem
    • 1
  • M. Schramm
    • 1
  1. 1.Bayer AG, Institute of PharmacologyWuppertal 1Germany

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