Biomaterial Database

Positive inotropic activity of the novel histamine H2-receptor agonist, amthamine, on the human heart in vitro. 1994

E Poli, and C Pozzoli, and I Spaggiari, and G Bertaccini

Institute of Pharmacology, University of Parma, School of Medicine, Italy.

1. We tested the novel thiazole derivative, amthamine, for its ability to stimulate histamine H2-receptors in the human myocardium. 2. Experiments were carried out on isolated, electrically-driven pectinate muscle segments, excised from atrial appendages of patients undergoing corrective heart surgery. 3. Amthamine (0.3-100 microM) induced a positive inotropic activity, resembling histamine in terms of potency and efficacy. In comparison, impromidine was 10-30 times more active than histamine and amthamine, but its maximum effect was significantly lower, while dimaprit was as effective as histamine, but 10 times less potent. 4. The selective histamine H2-blocker, famotidine antagonized in a competitive fashion the amthamine-induced positive inotropic effect. pA2 value of famotidine against amthamine (7.21 +/- 0.45) was close to that measured against histamine (6.88 +/- 0.31) in the same conditions. 5. The effect of amthamine was not modified by beta-adrenoceptor blockade, excluding direct or indirect sympathomimetic activities of the compound. 6. These data provide evidence that amthamine is a selective and full acting histamine H2-receptor agonist in the human heart in vitro.

UI	MeSH Term	Description	Entries
D002316	Cardiotonic Agents	Agents that have a strengthening effect on the heart or that can increase cardiac output. They may be CARDIAC GLYCOSIDES; SYMPATHOMIMETICS; or other drugs. They are used after MYOCARDIAL INFARCT; CARDIAC SURGICAL PROCEDURES; in SHOCK; or in congestive heart failure (HEART FAILURE).	Cardiac Stimulant,Cardiac Stimulants,Cardioprotective Agent,Cardioprotective Agents,Cardiotonic,Cardiotonic Agent,Cardiotonic Drug,Inotropic Agents, Positive Cardiac,Myocardial Stimulant,Myocardial Stimulants,Cardiotonic Drugs,Cardiotonics,Agent, Cardioprotective,Agent, Cardiotonic,Drug, Cardiotonic,Stimulant, Cardiac,Stimulant, Myocardial
D006325	Heart Atria	The chambers of the heart, to which the BLOOD returns from the circulation.	Heart Atrium,Left Atrium,Right Atrium,Atria, Heart,Atrium, Heart,Atrium, Left,Atrium, Right
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D013844	Thiazoles	Heterocyclic compounds where the ring system is composed of three CARBON atoms, a SULFUR and NITROGEN atoms.	Thiazole
D017442	Histamine Agonists	Drugs that bind to and activate histamine receptors. Although they have been suggested for a variety of clinical applications histamine agonists have so far been more widely used in research than therapeutically.	Histamine H1 Agonists,Histamine H2 Agonists,Histamine H3 Agonists,H1 Agonist,H1 Agonists,H2 Agonist,H2 Agonists,H3 Agonist,H3 Agonists,Histamine Agonist,Histamine H1 Agonist,Histamine H1 Receptor Agonist,Histamine H1 Receptor Agonists,Histamine H2 Agonist,Histamine H2 Receptor Agonist,Histamine H2 Receptor Agonists,Histamine H3 Agonist,Histamine H3 Receptor Agonists,Histaminergic Agonist,Histaminergic Agonists,Agonist, H1,Agonist, H2,Agonist, H3,Agonist, Histamine,Agonist, Histamine H1,Agonist, Histamine H2,Agonist, Histamine H3,Agonist, Histaminergic,Agonists, H1,Agonists, H2,Agonists, H3,Agonists, Histamine,Agonists, Histamine H1,Agonists, Histamine H2,Agonists, Histamine H3,Agonists, Histaminergic,H1 Agonist, Histamine,H1 Agonists, Histamine,H2 Agonist, Histamine,H2 Agonists, Histamine,H3 Agonist, Histamine,H3 Agonists, Histamine
D066298	In Vitro Techniques	Methods to study reactions or processes taking place in an artificial environment outside the living organism.	In Vitro Test,In Vitro Testing,In Vitro Tests,In Vitro as Topic,In Vitro,In Vitro Technique,In Vitro Testings,Technique, In Vitro,Techniques, In Vitro,Test, In Vitro,Testing, In Vitro,Testings, In Vitro,Tests, In Vitro,Vitro Testing, In