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Vatner SF, Franklin D, Braunwald E. Effects of anesthesia and sleep on circulatory response to carotid sinus nerve stimulation. Am J Physiol 1971; 220:1249-55. [PMID: 5574640 DOI: 10.1152/ajplegacy.1971.220.5.1249] [Citation(s) in RCA: 93] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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152
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Abstract
The effects of ouabain (G-strophanthin), 20 µg/kg were compared in 12 conscious dogs with Doppler flow transducers on the ascending aorta and left circumflex coronary artery and pressure gauges in the aorta, and in 9 of these dogs after general anesthesia with Na pentobarbital. In conscious dogs ouabain caused an initial bradycardia, but heart rate returned almost to control at 15 to 30 minutes, while arterial pressure rose and remained elevated. Cardiac output and coronary blood flow decreased initially, returned to control by 5 minutes and then remained constant. Systemic, mean, and late diastolic coronary resistances were elevated within 1 minute and remained elevated for 30 minutes. After anesthesia, ouabain caused similar increases in arterial pressure and slightly greater increases in systemic resistance, but the bradycardia and reduction of cardiac output were more profound and sustained. In the anesthetized state, coronary resistance rose when heart rate was allowed to slow after ouabain but was not elevated when heart rate was returned to control. Thus, in the conscious state, ouabain caused a distinct elevation in coronary and systemic resistances with no change in cardiac output, while in the anesthetized state ouabain reduced cardiac output and when heart rate was controlled, did not alter coronary resistance.
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153
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Vatner SF, Franklin D, VanCitters RL. Simultaneous comparison and calibration of the Doppler and electromagnetic flowmeters. J Appl Physiol (1985) 1970; 29:907-10. [PMID: 5488772 DOI: 10.1152/jappl.1970.29.6.907] [Citation(s) in RCA: 102] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
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154
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Vatner SF, Franklin D, Van Citters RL. Coronary and visceral vasoactivity associated with eating and digestion in the conscious dog. Am J Physiol 1970; 219:1380-5. [PMID: 5473122 DOI: 10.1152/ajplegacy.1970.219.5.1380] [Citation(s) in RCA: 57] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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155
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Vatner SF, Franklin D, Van Citters RL, Braunwald E. Effects of carotid sinus nerve stimulation on blood-flow distribution in conscious dogs at rest and during exercise. Circ Res 1970; 27:495-503. [PMID: 5507026 DOI: 10.1161/01.res.27.4.495] [Citation(s) in RCA: 89] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
The effects of stimulating the carotid sinus nerves on the distribution of cardiac output and peripheral vasoactivity was studied in intact, unanesthetized dogs instrumented with ultrasonic or electromagnetic flow probes on the ascending aorta, mesenteric, renal, and iliac arteries, and miniature pressure gauges in the aorta. A radiofrequency pacemaker was used to stimulate the nerves in dogs at rest, during treadmill exercise, and after autonomic blockade. Thirty-second periods of stimulation in the resting dog resulted in an average decrease in aortic pressure of 28%, cardiac output remained unchanged, total peripheral resistance fell 29%, mesenteric flow 12%, mesenteric vascular resistance 18%, renal flow 8%, and renal vascular resistance 22%. In the iliac bed flow increased by 90% while resistance declined by 62%. Heart rate decreased initially by 13%, and returned to control during stimulation. The bradycardia was determined to be predominantly due to vagal stimulation. During treadmill exercise carotid sinus nerve stimulation resulted in similar decreases in arterial pressure, mesenteric and renal resistance, and a further decrease in iliac resistance from exercise control values. Thus, electrical stimulation of the carotid sinus nerves in the conscious dog produced a differential pattern of peripheral vasodilatation, the most profound dilatation being observed in the hind-limb circulation. This release of sympathetic tone also occurred during stimulation in exercising animals when the muscular bed was already dilated on a metabolic basis.
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156
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Abstract
Control of the coronary circulation by the carotid sinus was studied in intact, unanesthetized dogs instrumented with Doppler ultrasonic flow probes on the left circumflex coronary artery, miniature pressure gauges in the aorta, and stimulating electrodes on the carotid sinus nerves. A radiofrequency pacemaker was used to stimulate the nerves in dogs at rest, during sleep, exercise, and after autonomic blockade. Thirty-second periods of stimulation in the resting conscious dog resulted in an average decrease in aortic pressure of 28%, an average decrease in mean coronary flow of 7%, while heart rate decreased by 13% at the beginning of stimulation and then returned to control levels. Mean and late diastolic coronary resistances decreased by an average of 22% from control. Similar results occurred with carotid sinus nerve stimulation during sleep and during treadmill exercise. Combined beta-receptor blockade with propranolol and atropine prevented the changes in heart rate with carotid sinus nerve stimulation but not the decrease in arterial pressure or the coronary dilatation. After alpha-receptor blockade with phenoxybenzamine or sympathetic blockade with guanethidine, coronary dilatation was not observed with carotid sinus nerve stimulation. Thus sympathetic constrictor tone is present in the resting conscious dog and the coronary dilatation observed with electrical stimulation of the carotid sinus nerves is due to a reduction in resting sympathetic constrictor tone.
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Franklin D. Ultrasonic techniques for measurement of blood flow. Pa Med 1970; 73:175-6. [PMID: 5418257] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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159
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160
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161
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162
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Benchimol A, Pedraza A, Maia IG, Gartlan JL, Vázquez Ibarra R, Franklin D. [Arterial flow telemetry in man using Doppler's ultrasonic flowmeters]. Arch Inst Cardiol Mex 1968; 38:818-29. [PMID: 5711374] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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163
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164
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Bruce RA, Lind AR, Franklin D, Muir AL, Macdonald HR, McNicol GW, Donald KW. The effects of digoxin on fatiguing static and dynamic exercise in man. Clin Sci (Lond) 1968; 34:29-42. [PMID: 5640684] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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165
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166
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Franklin D. Helmets and Body Armor in Modern Warfare. Science 1920. [DOI: 10.1126/science.52.1339.201-a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
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