Diverse Relaxation Responses of Canine Large and Small Conductive Coronary Arteries to Glyceryl Trinitrate and Nitric Oxide on the One Hand and to 8-Bromoguanosine 3’: 5’ Cyclic Monophosphate on the Other

Parker, Janet L., Mildred L. Mattox, and M. Harold Laughlin.Contractile responsiveness of coronary arteries from exercise trained rats. J. Appl. Physiol. 83(2): 434–443, 1997.—The purpose of this study was to determine whether exercise training alters vasomotor reactivity of rat coronary arteries. In vitro isometric microvessel techniques were used to evaluate vasomotor properties of proximal left anterior artery rings (1 ring per animal) from exercise-trained rats (ET; n = 10) subjected to a 12-wk treadmill training protocol (32 m/min, 15% incline, 1 h/day, 5 days/wk) and control rats (C; n = 6) restricted to cage activity. No differences in passive length-tension characteristics or internal diameter (158 ± 9 and 166 ± 9 μm) were observed between vessesls of C and ET rats. Concentration-response curves to K+ (5–100 mM), prostaglandin F2α(10−8–10−4M), and norepinephrine (10−8–10−4) were unaltered ( P > 0.05) in coronary rings from ET rats compared with C rats; however, lower values of the concentration producing 50% of the maximal contractile response in rings from ET rats ( P = 0.05) suggest that contractile sensitivity to norepinephrine was enhanced. Vasorelaxation responses to sodium nitroprusside (10−9-10−4M) and adenosine (10−9-10−4M) were not different ( P > 0.05) between vessels of C and ET rats. However, relaxation responses to the endothelium-dependent vasodilator acetylcholine (ACh; 10−10-10−4M) were significantly blunted ( P < 0.001) in coronary rings from ET animals; maximal ACh relaxation averaged 90 ± 5 and 46 ± 12%, respectively, in vessels of C and ET groups. In additional experiments, two coronary rings (proximal and distal) were isolated from each C ( n = 7) and ET ( n = 7) animal. Proximal coronary artery rings from ET animals demonstrated decreased relaxation responses to ACh; however, ACh-mediated relaxation of distal coronary rings was not different between C and ET groups. N G-monomethyl-l-arginine (inhibitor of nitric oxide synthase) blocked ACh relaxation of all rings. l-Arginine (substrate for nitric oxide synthase) did not improve the blunted ACh relaxation in proximal coronary artery rings from ET rats. These studies suggest that exercise-training selectively decreases endothelium-dependent (ACh) but not endothelium-independent (sodium nitroprusside) relaxation responses of rat proximal coronary arteries; endothelium-dependent relaxation of distal coronary arteries is unaltered by training.

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cGMP mediates the desensitization to bradykinin in isolated canine coronary arteries

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.1995.268.2.h865 ◽

1995 ◽

Vol 268 (2) ◽

pp. H865-H870 ◽

Cited By ~ 8

Author(s):

L. Olmos ◽

J. V. Mombouli ◽

S. Illiano ◽

P. M. Vanhoutte

Keyword(s):

Nitric Oxide ◽

Methylene Blue ◽

Coronary Arteries ◽

No Synthase ◽

Cyclic Monophosphate ◽

Prostaglandin F2 Alpha ◽

Relaxation Curves ◽

Synthase Inhibitor ◽

The Right ◽

Selective Impairment

The relaxation to bradykinin in canine coronary arteries is mediated by endothelium-derived nitric oxide (NO) and hyperpolarizing factor (EDHF). Desensitization to the kinin was induced by incubation of canine coronary arteries with endothelium with 10(-8) M bradykinin for 30 min. After washout, tissues were contracted with prostaglandin F2 alpha, and concentration-relaxation curves to bradykinin were obtained in control and desensitized arteries treated with indomethacin. After desensitization, there was a shift to the right of the concentration-relaxation curves to bradykinin. However, the elevation in guanosine 3',5'-cyclic monophosphate (cGMP) levels evoked by bradykinin was similar in both groups of tissues. The curves to bradykinin obtained in the presence of NG-nitro-L-arginine (an NO synthase inhibitor) were depressed, whereas those obtained in arteries contracted with potassium (to eliminate the EDHF-mediated relaxation) were not affected by the desensitization. Addition of NG-nitro-L-arginine, oxyhemoglobin, or methylene blue before the desensitization procedure preserved, whereas 3-morpholinosydnonimine (SIN-1, a donor of NO) and 8-bromoguanosine 3',5'-cyclic monophosphate impaired, the EDHF-mediated relaxation to bradykinin. Thus the selective impairment of the EDHF-dependent relaxation to bradykinin may be mediated by NO, acting mainly through increased production of cGMP.

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Chronic nitric oxide synthase inhibition blunts endothelium-dependent function of conduit coronary arteries, not arterioles

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.00899.2006 ◽

2007 ◽

Vol 292 (6) ◽

pp. H2798-H2808 ◽

Cited By ~ 8

Author(s):

David G. Ingram ◽

Sean C. Newcomer ◽

Elmer M. Price ◽

Kevin E. Eklund ◽

Richard M. McAllister ◽

...

Keyword(s):

Nitric Oxide ◽

Nitric Oxide Synthase ◽

Coronary Arteries ◽

Tap Water ◽

Group Differences ◽

Miniature Swine ◽

Relaxation Responses ◽

Oxide Synthase ◽

Coronary Arterioles

Current literature suggests that chronic nitric oxide synthase (NOS) inhibition has differential effects on endothelium-dependent dilation (EDD) of conduit arteries vs. arterioles. Therefore, we hypothesized that chronic inhibition of NOS would impair EDD of porcine left anterior descending (LAD) coronary arteries but not coronary arterioles. Thirty-nine female Yucatan miniature swine were included in the study. Animals drank either tap water or water with NG-nitro-l-arginine methyl ester (l-NAME; 100 mg/l), resulting in control and chronic NOS inhibition (CNI) groups, respectively. Treatment was continued for 1–3 mo (8.3 ± 0.6 mg·kg−1·day−1). In vitro EDD of coronary LADs and arterioles was assessed via responses to ADP (LADs only) and bradykinin (BK), and endothelium-independent function was assessed via responses to sodium nitroprusside (SNP). Chronic NOS inhibition diminished coronary artery EDD to ADP and BK. Incubating LAD rings with l-NAME decreased relaxation responses of LADs from control pigs but not from CNI pigs such that between-group differences were abolished. Neither indomethacin (Indo) nor sulfaphenazole incubation significantly affected relaxation responses of LAD rings to ADP or BK. Coronary arteries from CNI pigs showed enhanced relaxation responses to SNP. In contrast to coronary arteries, coronary arterioles from CNI pigs demonstrated preserved EDD to BK and no increase in dilation responses to SNP. l-NAME, Indo, and l-NAME + Indo incubation did not result in significant between-group differences in arteriole dilation responses to BK. These results suggest that although chronic NOS inhibition diminishes EDD of LAD rings, most likely via a NOS-dependent mechanism, it does not affect EDD of coronary arterioles.

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Antenatal betamethasone therapy potentiates nitric oxide-mediated relaxation of preterm ovine coronary arteries

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.1996.270.2.h538 ◽

1996 ◽

Vol 270 (2) ◽

pp. H538-H544 ◽

Cited By ~ 9

Author(s):

Y. Gao ◽

H. Zhou ◽

J. U. Raj

Keyword(s):

Nitric Oxide ◽

Coronary Arteries ◽

Soluble Guanylate Cyclase ◽

Calcium Ionophore ◽

Ringer Solution ◽

Isometric Tension ◽

Calcium Ionophore A23187 ◽

Ionophore A23187 ◽

Cyclic Monophosphate ◽

Endothelium Dependent Relaxation

The present study was designed to test the hypothesis that betamethasone may potentiate nitric oxide-mediated relaxation of coronary arteries of preterm lambs. Isolated coronary arteries were obtained from lambs delivered at 128 days gestation. The lambs were treated intramuscularly with a single dose of betamethasone or saline 48 h before delivery and were killed after 3 h of ventilation after delivery. Vessel rings were suspended in organ chambers filled with modified Krebs-Ringer solution (95% O2-5% CO2, 37 degrees C), and their isometric tension was recorded. The endothelium-dependent relaxation induced by bradykinin and calcium ionophore A23187 was greater in arteries from antenatal betamethasone-treated lambs than in arteries from control lambs. The relaxation was abolished by N omega-nitro-L-arginine. Nitric oxide induced a greater relaxation in vessels from antenatal betamethasone-treated lambs and in vessels preincubated with betamethasone than in vessels from controls. Coronary arteries from control and antenatal betamethasone-treated lambs relaxed similarly to 8-bromoguanosine 3',5'-cyclic monophosphate. Nitric oxide induced a greater increase in guanosine 3',5'-cyclic monophosphate content in coronary arteries from antenatal betamethasone-treated lambs than in arteries from control lambs. Our data suggest that antenatal betamethasone therapy potentiates nitric oxide-mediated relaxation in coronary arteries from preterm lambs, probably by affecting the activity of soluble guanylate cyclase of vascular smooth muscle cells.

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Note on Selection of Coordinate Systems for Geodynamics

International Astronomical Union Colloquium ◽

10.1017/s0252921100051174 ◽

1975 ◽

Vol 26 ◽

pp. 395-407

Author(s):

S. Henriksen

Keyword(s):

Sea Level ◽

The Other ◽

Coordinate Systems ◽

Mean Sea Level ◽

The Earth ◽

The One ◽

Static Systems ◽

Selection Of

The first question to be answered, in seeking coordinate systems for geodynamics, is: what is geodynamics? The answer is, of course, that geodynamics is that part of geophysics which is concerned with movements of the Earth, as opposed to geostatics which is the physics of the stationary Earth. But as far as we know, there is no stationary Earth – epur sic monere. So geodynamics is actually coextensive with geophysics, and coordinate systems suitable for the one should be suitable for the other. At the present time, there are not many coordinate systems, if any, that can be identified with a static Earth. Certainly the only coordinate of aeronomic (atmospheric) interest is the height, and this is usually either as geodynamic height or as pressure. In oceanology, the most important coordinate is depth, and this, like heights in the atmosphere, is expressed as metric depth from mean sea level, as geodynamic depth, or as pressure. Only for the earth do we find “static” systems in use, ana even here there is real question as to whether the systems are dynamic or static. So it would seem that our answer to the question, of what kind, of coordinate systems are we seeking, must be that we are looking for the same systems as are used in geophysics, and these systems are dynamic in nature already – that is, their definition involvestime.

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Stories and the Self

Journal of Media Psychology Theories Methods and Applications ◽

10.1027/1864-1105/a000255 ◽

2020 ◽

Vol 32 (2) ◽

pp. 47-58 ◽

Cited By ~ 1

Author(s):

Stefan Krause ◽

Markus Appel

Keyword(s):

Meta Analysis ◽

The Self ◽

The Other ◽

Lower Degree ◽

Contrast Effects ◽

Self Perception ◽

Self Perceptions ◽

Other Hand ◽

The One ◽

Implicit And Explicit

Abstract. Two experiments examined the influence of stories on recipients’ self-perceptions. Extending prior theory and research, our focus was on assimilation effects (i.e., changes in self-perception in line with a protagonist’s traits) as well as on contrast effects (i.e., changes in self-perception in contrast to a protagonist’s traits). In Experiment 1 ( N = 113), implicit and explicit conscientiousness were assessed after participants read a story about either a diligent or a negligent student. Moderation analyses showed that highly transported participants and participants with lower counterarguing scores assimilate the depicted traits of a story protagonist, as indicated by explicit, self-reported conscientiousness ratings. Participants, who were more critical toward a story (i.e., higher counterarguing) and with a lower degree of transportation, showed contrast effects. In Experiment 2 ( N = 103), we manipulated transportation and counterarguing, but we could not identify an effect on participants’ self-ascribed level of conscientiousness. A mini meta-analysis across both experiments revealed significant positive overall associations between transportation and counterarguing on the one hand and story-consistent self-reported conscientiousness on the other hand.

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Radioimmunotherapy for treatment of acute myeloid leukaemia and myelodysplastic syndrome

Nuklearmedizin ◽

10.1055/s-0038-1625714 ◽

2005 ◽

Vol 44 (03) ◽

pp. 107-117

Author(s):

R. G. Meyer ◽

W. Herr ◽

A. Helisch ◽

P. Bartenstein ◽

I. Buchmann

Keyword(s):

Acute Myeloid Leukaemia ◽

Myeloid Leukaemia ◽

Primary Tumour ◽

The Other ◽

Haematopoietic Stem Cell ◽

Other Hand ◽

Primary Reduction ◽

The One ◽

Acute Myeloid

SummaryThe prognosis of patients with acute myeloid leukaemia (AML) has improved considerably by introduction of aggressive consolidation chemotherapy and haematopoietic stem cell transplantation (SCT). Nevertheless, only 20-30% of patients with AML achieve long-term diseasefree survival after SCT. The most common cause of treatment failure is relapse. Additionally, mortality rates are significantly increased by therapy-related causes such as toxicity of chemotherapy and complications of SCT. Including radioimmunotherapies in the treatment of AML and myelodyplastic syndrome (MDS) allows for the achievement of a pronounced antileukaemic effect for the reduction of relapse rates on the one hand. On the other hand, no increase of acute toxicity and later complications should be induced. These effects are important for the primary reduction of tumour cells as well as for the myeloablative conditioning before SCT.This paper provides a systematic and critical review of the currently used radionuclides and immunoconjugates for the treatment of AML and MDS and summarizes the literature on primary tumour cell reductive radioimmunotherapies on the one hand and conditioning radioimmunotherapies before SCT on the other hand.

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Das Ende der Postdemokratie, den Pessimismus überwinden.

PROKLA Zeitschrift für kritische Sozialwissenschaft ◽

10.32387/prokla.v47i188.74 ◽

2017 ◽

Vol 47 (188) ◽

pp. 487-494

Author(s):

Daniel Mullis

Keyword(s):

Political Thought ◽

Social Dynamics ◽

Social Conditions ◽

The Other ◽

Economic Decline ◽

Far Right ◽

Windows Of Opportunity ◽

Political Events ◽

Political Struggles ◽

The One

In recent years, political and social conditions have changed dramatically. Many analyses help to capture these dynamics. However, they produce political pessimism: on the one hand there is the image of regression and on the other, a direct link is made between socio-economic decline and the rise of the far-right. To counter these aspects, this article argues that current political events are to be understood less as ‘regression’ but rather as a moment of movement and the return of deep political struggles. Referring to Jacques Ranciere’s political thought, the current conditions can be captured as the ‘end of post-democracy’. This approach changes the perspective on current social dynamics in a productive way. It allows for an emphasis on movement and the recognition of the windows of opportunity for emancipatory struggles.

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Tolerance is theoretical and practical principles

Ukrainian Religious Studies ◽

10.32420/1996.4.69 ◽

1996 ◽

pp. 13-23

Author(s):

Mykhailo Babiy

Keyword(s):

Religious Diversity ◽

The Other ◽

Nodal Points ◽

Characteristic Features ◽

The One ◽

Ukrainian Society

Political ideological pluralism, religious diversity are characteristic features of modern Ukrainian society. On the one hand, multiculturalism, socio-political, religious differentiation of the latter appear as important characteristics of its democracy, as a practical expression of freedom, on the other - as a factor that led to the deconsocialization of society, gave rise to "nodal points" of tension, confrontational processes, in particular, in political and religious spheres.

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The Salvage of Ideas: Schumpeter and the Core Problems Still Confronting Economics

Voprosy Ekonomiki ◽

10.32609/0042-8736-2003-11-15-26 ◽

2003 ◽

pp. 15-26

Author(s):

P. Wynarczyk

Keyword(s):

The Other ◽

The Core ◽

Other Hand ◽

The One

Two aspects of Schumpeter' legacy are analyzed in the article. On the one hand, he can be viewed as the custodian of the neoclassical harvest supplementing to its stock of inherited knowledge. On the other hand, the innovative character of his works is emphasized that allows to consider him a proponent of hetherodoxy. It is stressed that Schumpeter's revolutionary challenge can lead to radical changes in modern economics.

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