Histamine membrane receptors are defined as either H1 (blocked by diphenhydramine-like antagonists) or H2 (blocked by cimetidine-like agents). We now report the solubilization, separation, and partial characterization of specific H1 and H2 membrane receptors from calf thymocytes. Membrane fragments were incubated with [3H]histamine either alone or with unlabeled histamine, diphenhydramine, or c...

Quantum chemical (MNDo)caleulations have beenused toelucidate the molecular properties and structure - activity relationships of dihydropyridine (DHP) type calcium antagonists. There is a good corielation between the net atomic charges on various atoms of the 4 - phenyl ring of dihydropyridines and pharmacological activity. .Also, activity decreases with increasing free rotation of the phen...

in this study, the influence of dopamine receptor agonists and antagonists on antinociception induced by bac10fen has been examined in the formalin test. the gaba-b agonist bac10fen induced antinociception in both phases of the formalin test in mice. the dopamine receptor agonists skf 38393 and quinpirole also induced antinociception in both phases of the test. skf 38393 but not quinpirole pote...

1. Rat histamine H2 receptors were epitope-tagged with six histidine residues at the C-terminus to allow immunological detection of the receptor. Recombinant baculoviruses containing the epitope-tagged H2 receptor were prepared and were used to infect insect Sf9 cells. 2. The His-tagged H2 receptors expressed in insect Sf9 cells showed typical H2 receptor characteristics as determined with [125...

In the 1970s, the identification of the histamine H2-receptor by Black and the subsequent development of histamine H2-receptor antagonists revolutionized our understanding and treatment of acid/peptic disorders. More recently, the identification of hydrogen-potassium-stimulated adenosine triphosphatase (H+/K(+)-ATPase) as the proton pump of the parietal cell and the recognition of the prominent...

We have investigated the effect of a bolus injection of atracurium 0.6 mg kg-1 on the cardiovascular system in 16 patients undergoing aortocoronary bypass surgery. H1- and H2-receptor antagonists were administered to eight patients before the neuromuscular blocker. A standard anaesthetic was used comprising fentanyl, flunitrazepam, etomidate and enflurane. After administration of atracurium, ha...

  In this study, we investigated the effect of nicotinic receptor agonists and antagonists on the analgesic response to morphine in the formalin test. In experiments conducted in mice, nicotine produced an early dose-dependent analgesic effect. At a dose of 0.5 mg/kg, mecamylamine, a nicotinic receptor inhibitor, suppressed the analgesic effect induced by 0.1 mg/kg nicotine in both stages of th...

This paper reviews the remarkable impact of H2-receptor antagonists on duodenal ulcer management. The development and the scientific rationale of these agents are presented, and efficacy and safety aspects in the short- and long-term treatment of duodenal ulcer disease discussed. Attention is focused on the possible role of "acid rebound" in ulcer relapse following the withdrawal of therapy and...

To assess the healing and relapse rate of duodenal ulcer (DU) treated with H2 receptor antagonists in helicobacter pylori (HP) positive vs negative cases, we analysed 95 cases of endoscopically proven duodenal ulcer. H. pylori colonization was found in 73 (77%) patients before treatment. No difference was observed in the pre-treatment characteristics between patients with HP positive and HP neg...