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Updated: Aug 14, 2026

Drug-induced Sensitization of Adenylyl Cyclase: Assay Streamlining and Miniaturization for Small Molecule and siRNA Screening Applications
Published on: January 27, 2014
Cardiovascular studies with impromidine (SK&F 92676), a new very potent and specific histamine H2-receptor agonist
Abstract:
Impromidine (SK & F 92676) has recently been identified as a potent and specific histamine H2-receptor agonist. The present paper describes some cardiovascular studies with the drug. Impromidine lowers blood pressure in cats and rats by interaction with H2-receptors. During continuous intravenous infusions of impromidine, the fall in blood pressure is due to a reduction in total peripheral resistance; cardiac output increases during hypotension. The responses to impromidine are similar to responses to histamine in mepyramine-treated cats. Impromidine administered intra-arterially also causes vasodilatation in the femoral and mesenteric vasculature by interaction with H2-receptors. Impromidine stimulates all measured parameters including coronary flow in the isolated working heart of the guinea-pig. Dose-response curves to impromidine were displaced to the right in the presence of cimetidine.
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