title: Pharmacological investigations of 4-ethoxy-2-methyl-5-morpholino-3(2H)-pyridazinone (M 73101), a new analgesic and anti-inflammatory drug.
abstract: Analgesic, anti-inflammatory and other related actions of 4-ethoxy-2-methyl-5-morpholino-3(2H)-pyridazinone (M73101) were investigated in experimental animals, and the following results were obtained: Analgesic activity of M73101 was more potent than that of other anti-inflammatory drugs except for aminopyrine in phenylquinone test in mice. M73101 showed the most potent analgesic activity among the drugs tested in Randall-Selitto test in rats. The mode of analgesic action of M73101 resembled that of aminopyrine. M73101 possessed potent inhibitory activities on acute inflammatory edema and suppressed the permeability of capillary vessels. M73101 inhibited histamine release from isolated rat mast cells (in vitro) and rat skin (in vivo) by the condensation product of N-methyl-homoanisylamine formaldehyde (compound 48/80), and leucocyte emigration in carrageenin rat pleurisy. M73101 was much less active than phenylbutazone and other anti-inflammatory drugs in causing gastric lesion. Considering from therapeutic index, M73101 was found to be much superior to mepirizole, tiaramide, benzydamine, phenylbutazone and acetylsalicylic acid.
mesh_terms: D000251:Adenosine Triphosphatases / Q000378:metabolism; D000818:Animals; D000894:Anti-Inflammatory Agents, Non-Steroidal; D055598:Chemical Phenomena; D002621:Chemistry; D016861:Cyclooxygenase Inhibitors; D005938:Glucocorticoids / Q000378:metabolism; D006168:Guinea Pigs; D006636:Histamine Release / Q000187:drug effects; D066298:In Vitro Techniques; D007509:Irritants; D008099:Liver / Q000378:metabolism; D008297:Male; D051379:Mice; D008815:Mice, Inbred Strains; D011724:Pyridazines / Q000494:pharmacology*; D051381:Rats; D011919:Rats, Inbred Strains; D012018:Reflex / Q000187:drug effects
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D016861:Cyclooxygenase Inhibitors; D005938:Glucocorticoids; D007509:Irritants; D011724:Pyridazines; D000251:Adenosine Triphosphatases; C018432:emorfazone