Pre- and postsynaptic alpha-2 adrenoceptors as target for drug discovery

  • S. Z. Langer
  • I. Angel
Conference paper
Part of the Journal of Neural Transmission book series (NEURAL SUPPL, volume 34)


The presynaptic terminal autoreceptors which modulate the release of noradrenaline through a negative feed-back mechanism correspond to the α2-subtype of adrenoceptors. These receptors are also present post- synaptically in the pancreatic islets were they mediate inhibition of the glucose- induced release of insulin. The sympathetic innervation of the pancreatic islets involves α2-adrenoceptors both presynaptically as well as postsynaptically. SL 84.0418 is a novel α2-adrenoceptor antagonist with preferential effects in the periphery and with at least a 10-fold higher selectivity ratio between α2 and ar adrenoceptors when compared with idazoxan. SL 84.0418 antagonizes the hyperglycemia and the inhibition of insulin release induced by the α2- adrenoceptor agonist UK 14304. The administration of SL 84.0418 significantly reduces the glucose evoked hyperglycemia in several species including man. It is proposed that SL 84.0418 may represent a useful and novel hypoglycemic drug in the treatment of type II diabetes.


Insulin Release Selectivity Ratio Rabbit Pulmonary Artery Canine Saphenous Vein High Selectivity Ratio 
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Copyright information

© Springer-Verlag 1991

Authors and Affiliations

  • S. Z. Langer
    • 1
  • I. Angel
    • 1
  1. 1.Department of BiologySynthélabo Recherche (LERS)Paris Cédex 13France

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