Biomedical subjects

Muneyasu Saito

Publications and source records attributed to Muneyasu Saito.

40 records · Page 3Linked to original sources

PubMed2002

Nicorandil and leukocyte activation.

Nicorandil, a hybrid compound of an ATP-sensitive potassium (KATP ) channel opener and a nitric oxide donor, has been reported to preserve microvascular integrity in patients with reperfused myocardial infarction. The aim of the current study was to test the hypothesis that nicorandil suppresses activation of polymorphonuclear leukocytes (PMNLs), resulting in reduction of PMNL migration into tissue upon ischemia/reperfusion. Nicorandil, along with the mitochondrial KATP channel opener diazoxide and the nitric oxide donors nitroglycerin and isosorbide dinitrate, suppressed pseudopod projection in human PMNLs treated with 10(-9)-formyl-methionyl-leucyl-phenylalanine (FMLP) and subjected to shear stress (5 dyn/cm(2)) with a cone-and-plate shear device. Suppression by nicorandil and diazoxide was reversed by KATP channel blockers, 5 hydroxydecanoate and glibenclamide. FMLP-induced increase of [Ca2+] in PMNLs was suppressed by nicorandil and diazoxide, and 5 hydroxy-decanoate and glibenclamide reversed this suppression. Results of reverse transcription polymerase chain reaction with rat PMNL mRNA indicated the presence of mRNAs of Kir6.2 and Kir6.1 but not mRNAs of sulfonylurea receptor 1 or 2. Isosorbide dinitrate, diazoxide, and nicorandil reduced leukocyte migration and microvascular obstruction in reperfused ischemic tissue of rat mesenteric microcirculation. In conclusion, nicorandil attenuates ischemia/reperfusion-induced PMNL activation via donation of nitric oxide and K channel-related cascade.

Animals↗

PubMed2002

Rupture of the anterolateral papillary muscle caused by a single diagonal branch obstruction.

This report presents the first case of anterolateral papillary muscle rupture caused by a diagonal branch occlusion only. Although the patient was in shock on admission, he was successfully treated by emergency surgery after hemodynamic stabilization by a percutaneous cardiopulmonary support system. This case implies that the anterolateral papillary muscle has a single blood supply and that it can rupture by an occlusion of only one diagonal branch even after balloon angioplasty.

Aged↗

PubMed2002

[Serotonin receptor blockade effective for postprandial vasospastic angina associated with dumping syndrome after esophagectomy: a case report].

A 49-year-old woman was admitted to our hospital because of frequent postprandial esophageal angina. After successful pyloric plasty, chest oppression lasting 5 to 15 min developed postprandially as well as symptoms of dumping syndrome. Electrocardiography showed ST-segment elevation in the II, III, aVf and precordial leads (V2 to V6). Finally, giant positive T waves and U waves were uniquely noted in the V1 to V5 leads. Intracoronary administration of acetylcholine (20 micrograms) provoked severe diffuse spasm in both right and left coronary arteries, chest pain and ST elevation. The conventional treatment for vasospastic angina, such as Ca2+ antagonists, nitrates and K channel opener, achieved no response. However, the combination with serotonergic receptor blockade reduced anginal attack. These findings suggest that the spastic angina in this case was partly caused by serotonin.

Angina Pectoris↗

PubMedDate not supplied

Noninvasive tissue characterization of coronary arterial plaque by 16-slice computed tomography in acute coronary syndrome.

Noninvasive characterization of coronary plaques is challenging for cardiologists. The authors' goal was to explore the clinical feasibility of newly developed 16-slice computed tomography (CT) in tissue characterization of coronary arterial plaques in patients with acute coronary syndrome. Sixteen patients with acute coronary syndrome underwent 16-slice CT (Aquillion, Toshiba) and coronary arteriography with intravascular ultrasound (IVUS) within 7 days. Twenty-three plaques were classified by IVUS according to plaque echogenicity: 6 soft plaques, 11 intermediate plaques, and 6 calcified plaques. Mean (+/- SD) CT numbers (Hounsfield units [HU]) of these 3 types of plaques were 50.6 +/-14.8 HU, 131 +/-21.0 HU, and 721 +/-231 HU, respectively. Sixteen-slice CT facilitates noninvasive tissue characterization of coronary arterial plaques.

Adult↗