Are you Mitsugu Omata?

Claim your profile

Publications (2)2.14 Total impact

  • Mitsugu Omata · Naoko Matsui · Norio Inomata · Tomochika Ohno
    [Show abstract] [Hide abstract]
    ABSTRACT: We tested whether polysaccharide fucoidin, which inhibits leukocyte rolling in the mesenteric venule, has protective effects in the rat myocardial 30-min ischemia and 6-h reperfusion injury model. Intravenous infusion of fucoidin (27 microg/kg/min from 10 min before to 6 h after reperfusion) significantly attenuated myocardial infarct size 6 h after reperfusion. In this ischemia and reperfusion heart model, expression of P-selectin (determined immunohistochemically) was observed on the venular endothelial cells in the heart 30 min after reperfusion and also was sustained after 6 h. Neutrophil infiltration as estimated by myeloperoxidase activity significantly increased 2 h after reperfusion and kept increasing with time until 6 h after reperfusion. Four-hour infusion of fucoidin after reperfusion significantly reduced neutrophil infiltration, whereas the 2-h infusion of fucoidin did not. These results indicate that neutrophil infiltration and myocardial injury are attributed to expression of P-selectin after reperfusion, and that one of the inhibitory mechanisms of fucoidin seems to be blockade of P-selectin-mediated neutrophil rolling on the vessel wall.
    Journal of Cardiovascular Pharmacology 01/1998; 30(6):717-24. DOI:10.1097/00005344-199712000-00003 · 2.14 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: The cardiovascular and diuretic actions of carperitide were studied in experimental animals. Carperitide relaxed various canine arteries and veins that were contracted by high K+ or norepinephrine. Carperitide stimulated particulate guanylate cyclase from rat thoracic aortas. Carperitide had almost no effect on coronary perfusion pressure or heart rate, but caused a slight decrease in contractile force in isolated guinea pig hearts. Carperitide tended to decrease isoproterenol-induced renin release from isolated rat kidney slices and elicited decreases in angiotensin II-induced aldosterone release from bovine zona glomerulosa cells. Intravenous injection of carperitide elicited decreases in arterial blood pressure and total peripheral resistance in the anesthetized and conscious dogs. Carperitide also elicited transient increases in cardiac output and coronary blood flow followed by slight decreases in them. Intravenous infusion of carperitide elicited decreases in pulmonary capillary wedge pressure, pulmonary pressure and right atrial pressure in association with elevating plasma carperitide (ANP like immuno-reactivity) level in dogs with heart failure induced by coronary artery occlusion and saline loading. These results suggest that carperitide decreases both preload and afterload and can improve the untoward hemodynamic alterations in animals with acute experimental heart failure.
    Folia Pharmacologica Japonica 06/1993; 101(5):309-25. DOI:10.1254/fpj.101.5_309