Electrophysiology of Dihydropyridine Calcium Agonists

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

Abstract

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.

Keywords

Penicillin MgCl Streptomycin HEPES Cardiol 

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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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