+ Resolve Article
+ Follow Us
Follow on FacebookFollow on Facebook
Follow on TwitterFollow on Twitter

+ Translate
+ Subscribe to Site Feed
GeoScience Most Shared ContentMost Shared Content

Effects of nitroglycerin on regional myocardial ischemia induced by atrial pacing in dogs

, : Effects of nitroglycerin on regional myocardial ischemia induced by atrial pacing in dogs. Circulation Research 48(4): 569-576

The exact mechanism or mechanisms by which nitroglycerin exerts its beneficial effect on pacing-induced regional myocardial ischemia has not been ellucidated previously. In an open-chest, anesthetized canine preparation a fixed, flow limiting stenosis was applied to the left anterior descending (LAD) coronary artery and heart rate was increased by atrial pacing. Mass spectrometry was used to measure myocardial oxygen (PmO2) and carbon dioxide (PmCO2) tensions. Myocardial blood flow was measured by the radioactive microsphere technique. Application of the stenosis resulted in regional decreases in PmO2 and increases in PmCO2 of greater magnitude in the subendocardial than in the subepicardial layer. Atrial pacing resulted in a further decrease in PmO2 and increase in PmCO2 as well as a reduction in subendocardial blood flow. Nitroglycerin (TNG) infusion reduced mean arterial pressure 20 mm Hg, resulting in a 14 mm Hg reduction in PmCO2 in the more ischemic subendocardial layer (P less than 0.05). Myocardial blood flow decreased in all regions; however, the magnitude of this decrease was less in the ischemic region. Addition of aortic constriction abolished both the afterload and preload lowering effects of nitroglycerin but improved ischemic zone blood flow. These data demonstrate that nitroglycerin reduces the severity of pacing-induced regional myocardial ischemia primarily by reducing the determinants of myocardial oxygen demand. We found that when these effects are counteracted, improvement in myocardial oxygen supply becomes the dominant mechanism.


PMID: 6780231

Other references

Danilov V.V., 1986: Data processing of pump tests using the finite difference method. Izvestiya Vysshikh Uchebnykh Zavedeniy Geologiya i Razvedka

Igea, J.M.; von Pirquet Freiher, C., 2013: The history of the idea of allergy. About 100A years ago, a young paediatrician understood that the function of the immune system should be rationalized not in terms of exemption of disease but in terms of change of reactivity. He coined a new word to represent such an idea: a aller...

Kripfgans, O.D.; Rubin, J.M.; Hall, A.L.; Fowlkes, J.Brian., 2006: Vector Doppler imaging of a spinning disc ultrasound Doppler phantom. Vector Doppler methods are used to obtain angle independent in-plane velocity information. Velocity magnitude as well as direction are reconstructed from regular steered colour flow and front split-aperture Doppler acquisitions. Spatially resolved...

Shin NaRi; Kim JongMan; Yoo HanSang, 2000: Control of pig respiratory disease using egg yolk antibodies. I. Analysis of immunogens of Bordetella bronchiseptica, Pasteurella multocida and Actinobacillus pleuropneumoniae and production of IgY. Pig respiratory disease have caused severe economic losses in the pig industry worldwide. Several methods were developed and applied to prevent and control the disease. However, the problem still prevails in the pig industry. Recently, the use of...

Harris T.J.R., 1990: Molecular biology in drug discovery. Abstracts of Papers American Chemical Society 200(1-2): MEDI 85

Schuette, H.R.; Bohlmann, F.; Reusche, W., 1961: The biosynthesis of sparteine. Archiv der Pharmazie 294/66: 610-615

Kimura A., 1982: Iteological gleanings 2. Journal of Japanese Botany 57(6): 161-165

Awazu, M.; Nakano, Y.; Takeuchi, Y., 1982: Two cases of benign tertian malaria. Two cases of Plasmodium vivax malaria imported into Japan from Papua New Guinea are reported in adolescents. Both patients had taken chloroquine prophylaxis and had developed fever about a month after its discontinuation. Both were treated success...

Barry, S.J.E.; Zeger, S.L.; Selnes, O.A.; Grega, M.A.; Borowicz, L.M.; McKhann, G.M., 2005: Quantitative methods for tracking cognitive change 3 years after coronary artery bypass surgery. The analysis and interpretation of change in cognitive function test scores after coronary artery bypass grafting (CABG) present considerable statistical challenges. Application of hierarchical linear statistical models can estimate the effects of...

Petrov, R.V.; Shvets, V.N.; Man'ko, V.M., 1972: Change in stem-cell differentiation from erythroid type to myeloid type due to lymphocytes. Doklady Akademii Nauk SSSR 204(2): 489-492