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K Shikano

Publications and source records attributed to K Shikano.

33 records · Page 2Linked to original sources
PubMed1987

Differential selectivity of endothelium-derived relaxing factor and nitric oxide in smooth muscle.

The selectivity of endothelium-derived relaxing factor (EDRF) and nitric oxide (NO) on smooth muscle relaxation was examined and compared. EDRF released from was examined and compared. EDRF released from bovine pulmonary arterial endothelium (BPAE) in culture and NO were superfused over vascular, tracheal, gastrointestinal and uterine smooth muscle. EDRF relaxed vascular smooth muscle but not tracheal, gastrointestinal or uterine smooth muscle. NO relaxed vascular and gastrointestinal smooth muscle but not tracheal or uterine smooth muscle. There was a differential selectivity between the relaxant effect of EDRF and NO on smooth muscle.

Animals↗
PubMed1987

Endothelium-derived relaxing factor is a selective relaxant of vascular smooth muscle.

The present study examines the relaxant selectivity of endothelium-derived relaxing factor (EDRF) released from cultured endothelial cells. Endothelial cells from bovine pulmonary artery (CCL-209) in culture were grown on Cytodex-3 microcarrier beads, packed into a column and superfused to release EDRF. EDRF response was estimated by its ability to relax phenylephrine-contracted rings of rabbit aorta. Bradykinin and A23187 (10(-10) to 10(-6) M) caused dose-dependent release of EDRF from cultured bovine pulmonary artery endothelial cells. The release was dependent on endothelial cell number. A23187 caused a larger and longer-lasting release of EDRF than bradykinin. EDRF relaxation was selective for blood vessels. EDRF relaxed rabbit aortic rings, but it did not relax histamine-contracted guinea pig tracheal, rabbit taenia coli strips or oxytocin-contracted guinea pig uterine rings. These nonvascular smooth muscles were, however, relaxed by isoproterenol (10(-4) M) and sodium nitroprusside (SNP, 10(-5) M). The sensitivity of guinea pig aortic rings and tracheal strips to SNP were compared. The IC50 values for SNP (10(-9) to 10(-5) M) were 0.07 and 0.3 microM for aortic rings and tracheal strips, respectively. Although the tracheal strips were about 4-fold less sensitive than the aorta toward SNP, a complete relaxation was achieved. These results suggest that EDRF relaxes vascular smooth muscles but not respiratory, Gl or reproductive smooth muscles. Thus, EDRF may be a selective relaxant of vascular smooth muscle.

Animals↗
PubMed1986

Protective effects of the calmodulin antagonist bepridil on ischaemia induced in the rat myocardium.

The effects of a block of the slow calcium channel by bepridil and its antagonising effects on calmodulin were determined in the ischaemic rat myocardium. When isolated rat hearts were treated with a cardioplegic solution containing bepridil or verapamil there was a significant diminution in ischaemic damage in the myocardium. Bepridil was more effective than verapamil in protecting against this ischaemic damage. Bepridil effectively inhibited the activation of calmodulin dependent enzymes, such as calcium calmodulin dependent cyclic nucleotide phosphodiesterase and myosin light chain kinase. The inhibitory effect of verapamil on these enzymes was weaker than that of bepridil. Since bepridil protects the myocardium and minimises ischaemia induced damage these events might be related to a calmodulin antagonistic action as well as a calcium channel blocking action.

2',3'-Cyclic-Nucleotide Phosphodiesterases↗
PubMedDate not supplied

Endometrial cytodiagnosis with the Uterobrush and Endocyte.

OBJECTIVE: To compare two endometrial cytologic sampling devices, the Uterobrush and Endocyte, for their clinical applicability. STUDY DESIGN: Specimen collection and comparison in 60 women. RESULTS: Collection of specimens with both devices succeeded in 100% of cases and was practically painless. The cells' appearance with the Endocyte tended to be dense. Nevertheless, the amount of cells collected with both devices was adequate for diagnosis except in a few cases. CONCLUSION: The Uterobrush method is simple and painless and therefore very acceptable to patients and suitable for clinical use.

Adult↗
PubMedDate not supplied

Preoperative evaluation and surgical treatment for tricuspid regurgitation associated with acquired valvular heart disease. The Kay-Boyd method vs the Carpentier-Edwards ring method.

This study compared the results of annuloplastic repair of tricuspid regurgitation (TR) using Doppler echocardiography. Sixty-three patients who underwent tricuspid annuloplasty were studied. Thirty-four patients received Kay-Boyd annuloplasty and 29 Carpentier-Edwards ring annuloplasty. A new classification of TR based on the direction and area of regurgitation flow on Doppler echocardiogram was applied preoperatively. In the Kay-Boyd group, 10 cases showed massive TR and 24 cases showed localized TR preoperatively. Localized TR was well controlled in all cases, but 8 of 9 cases of massive TR showed grade III residual TR. In the C-E group, 21 cases showed massive TR and 8 cases showed localized TR. All cases were well controlled postoperatively. We conclude that (1) although the Kay-Boyd method is acceptable for localized TR, the C-E method should be employed for massive TR; (2) analyzing the regurgitant pattern of TR by Doppler echocardiogram is useful in selecting an appropriate surgical technique.

Adult↗