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Alpha adrenergic antagonism by cyclosporine
G W Parkhurst1, A V Prancan, B H Moon
1Department of Pharmacology, Rush Medical College, Chicago, Illinois 60612.
Abstract:
Cyclosporine has been shown to exert antiadrenergic actions in previous studies from this laboratory. Interactions of CsA with the alpha-one and alpha-two receptor were studied in rabbits. Blood pressure studies revealed that CsA exerts a competitive, reversible antagonism against norepinephrine, epinephrine, and phenylephrine. Further studies of heart rate depression by clonidine also demonstrated that CsA antagonizes this action. In conclusion, cyclosporine appears to act as a nonspecific alpha antagonist.
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