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Regulation of large coronary vessels by adrenergic mechanisms in conscious dogs


, : Regulation of large coronary vessels by adrenergic mechanisms in conscious dogs. Basic Research in Cardiology 76(5): 508-517

The effects of .alpha.- and .beta.-adrenergic stimulation were examined in conscious dogs on measurements of left circumflex coronary blood flow and coronary arterial diameter and on calculations of mean coronary resistance (MCR) and left circumflex coronary internal cross-sectional area (CSA). Methoxamine (50 .mu.g/kg per min), after transiently increasing left circumflex coronary dimensions, induced sustained reductions in left circumflex coronary diameter (9 .+-. 2%) and CSA (27 .+-. 5%) at a time when mean arterial pressure rose by 65 .+-. 5%, left ventricular (LV) dP/dt [change in pressure over time] had decreased only slightly, and heart rate and mean coronary blood flow were at control levels. Isoproterenol (0.1 .mu.g/kg per min) increased heart rate by 66 .+-. 8%, LV dP/dt by 58 .+-. 5%, and CSA by 17 .+-. 3%, while it decreased mean arterial pressure by 12 .+-. 1% and MCR by 44 .+-. 5%. After .beta.1-adrenergic receptor blockade and with heart rate held constant, isoproterenol did not increase LV dP/dt but decreased mean arterial pressure similarly (13 .+-. 2%) and induced attenuated increases in CSA (6 .+-. 1%), and decreases in MCR (17 .+-. 3%). After combined .beta.1- and .beta.2-adrenergic receptor blockades isoproterenol induced no significant effects. In the conscious dog, large coronary vessels not only react passively to changes in aortic pressure but also undergo substantial active changes. .alpha.-Adrenergic stimulation is sufficiently powerful to reduce CSA, despite the opposing elevation of distending pressure. Large vessels appear to be regulated by .beta.1-adrenergic mediated increase in myocardial metabolic demands and by .beta.2-adrenergic mediated vasodilation.

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Accession: 006288964

PMID: 6272684

DOI: 10.1007/bf01908352

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Bergh T.; Nillius S.J.; Wide L., 1979: Bromocriptine treatment of 7 women with primary amenorrhea and prolactin secreting pituitary tumors. Seven women with primary amenorrhea and hyperprolactinemia were treated with bromocriptine. All the women had started to develop secondary sex characteristics at normal age but pubertal development stopped and menarche did not occur. Radiological...

Chambers, C.B., 1975: Uterine prolapse with incarceration. American Journal of Obstetrics and Gynecology 122(4): 459-462

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Scott, E. O. G., 1960: Observations on some Tasmanian fishes IX. A case of mass mortality in Navodon setosus (Waite), 1899 [Aluteridae], a species now first formally recorded from Tasmania, is reported some features of two juveniles are described and figured. Taxonomic data on Mitotichthys tuckeri (Scott), 1942...

Clark R.V.; Seaman W.L.; Clough K.S.; Stirling J.D.E., 1979: Leaf blotch on barley hordeum vulgare cultivar laurier. An unusual leaf blotch was observed on 'Laurier' barley at several locations in eastern Canada. It was prevalent in late June and early July 1976 when high daytime temperatures and, in Ontario, high relative humidity levels were experien...

Tsai, C.S.; Hsu, P.C.; Huang, G.S.; Lin, T.C.; Hong, G.J.; Shih, C.M.; Li, C.Y., 2004: Midazolam attenuates adenosine diphosphate-induced P-selectin expression and platelet-leucocyte aggregation. Background and objective: The expression of P-selectin on the surface of platelets and platelet-leucocyte conjugate formation are considered to be an indicator of platelet activation in thrombotic and inflammatory disease. Midazolam is a widely us...

Mohr, J.; Cvan der Meer., 1941: Biologische waarnemingen bij pantai tjermin 111 Opeenhoopingen von Cerithidea obtusa p 53 fig Trop. Natuur Weltevreden, 304: 49-55

Shigenobu, M.; Senoo, Y.; Teramoto, S., 1988: Results of surgery for aortic regurgitation due to aortic valve prolapse. The clinical, hemodynamic and pathological findings of 13 patients with aortic regurgitation due to aortic valve prolapse caused by advanced myxomatous degeneration were evaluated. Eleven patients showed a favorable outcome with no complications r...

Rangarajan, C., 1994: Banking with the poor. This paper examines credit provision for the poor in India and how the poor can help themselves. A number of programmes have been designed specifically to enlarge the flow of credit to the poor. The main thrust of these programmes has been to prov...

Dunn, E. H., 1976: The relationship between brood size and age of effective homeo thermy in nestling house wrens. Altricial birds when hatched are not able to maintain a constant body temperature, and the ability to thermoregulate develops gradually during the first weeks of life. The age at which a single nestling can thermoregulate at ambient temperatures b...