Effect of changes in carotid sinus pulse pressure on catecholamine blood levels

1963 ◽  
Vol 204 (3) ◽  
pp. 467-470 ◽  
Author(s):  
Jiro Nakano ◽  
Christian De Schryver
Keyword(s):  
Pulse Pressure ◽  
Plasma Levels ◽  
Carotid Sinus ◽  
Blood Levels ◽  
Arterial Pulse ◽  
Arterial Blood ◽  
The Common ◽  
The Mean ◽  
Common Carotid Arteries

A study was made on the effect of changes in arterial pulse pressure per se on catecholamine secretion in the anesthetized dog. "Elasticity" bottles were inserted bilaterally in the common carotid arteries in order to change the magnitude of the pulse pressure in the carotid sinus areas without changing the mean arterial blood pressure. It was observed that a marked decrease in the pulse pressure resulted in significant increases in heart rate ( P < 0.005) and catecholamine plasma levels ( P < 0.005). The mechanism and role of this increase in plasma levels of catecholamines are discussed.

Role of sinoaortic reflexes in hemodynamic patterns of natural defense behaviors in the cat

1981 ◽  
Vol 240 (3) ◽  
pp. H421-H429 ◽  
Author(s):  
G. Baccelli ◽  
R. Albertini ◽  
A. Del Bo ◽  
G. Mancia ◽  
A. Zanchetti
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Cardiac Output ◽  
Carotid Sinus ◽  
Emotional Behavior ◽  
Natural Defense ◽  
Arterial Blood ◽  
Hemodynamic Pattern ◽  
Before And After

To evaluate whether sinoaortic afferents contribute to the hemodynamic pattern of fighting, cardiovascular changes associated with fighting were studied in cats before and after sinoaortic denervation. Sinoaortic denervation exaggerates the decrease in heart rate, cardiac output, and arterial pressure during immobile confrontation (hissing, staring but no movement). During nonsupportive fighting (fighting with forelimbs while lying on one side) and supportive fighting ( fighting while standing on four feet) sinoaortic denervation reduces the increase in heart rate and cardiac output, minimizes the mesenteric vasoconstriction, induces a fall in arterial blood pressure, but does not affect iliac vasoconstriction or vasodilatation. The hemodynamic pattern of fighting is similarly changed by temporary inactivation of carotid sinus baroreflexes by common carotid occlusion as by chronic section of sinoaortic nerves. It is concluded that sinoaortic reflexes play an important role in the cardiovascular patterns accompanying natural fighting. They favor cardiac action and allow a marked visceral vasoconstriction to occur, thus minimizing or preventing a fall in blood pressure during emotional behavior.

THE CARDIAC OUTPUT AND CAROTID AND TIBIAL BLOOD PRESSURE OF THE TURKEY

1963 ◽  
Vol 41 (11) ◽  
pp. 2337-2341 ◽  
Author(s):  
Elwood W. Speckmann ◽  
Robert K. Ringer
Keyword(s):  
Body Weight ◽  
Cardiac Output ◽  
Pulse Pressure ◽  
Mature Male ◽  
Systemic Resistance ◽  
Hemodynamic Parameters ◽  
Radioactive Phosphorus ◽  
Arterial Blood ◽  
Tibial Arteries ◽  
The Mean

The cardiac output of untreated mature male Broad Breasted Bronze (BBB) turkeys was determined by an isotope dilution technique using radioactive phosphorus (P32). A Geiger–Mueller tube was connected to a rate meter which in turn was connected to a moving graph to continuously record the indicator concentration, thus obtaining the initial dilution curve. Posterior tibial and common carotid arterial blood pressures were measured directly and were recorded simultaneously with the cardiac output determinations by means of two strain gauges connected to a recording polygraph.From the cardiovascular measurements systemic resistance was calculated. The mean cardiac output of the mature male BBB turkey was 231 ml per kg body weight0.734 per minute. The mean carotid hemodynamic parameters were: systolic BP, 302 mm Hg; diastolic BP, 204 mm Hg; and pulse pressure, 98 mm Hg. Heart rate was 149 beats per minute. The mean tibial hemodynamic parameters were; systolic BP, 286 mm Hg; diastolic BP, 200 mm Hg; and pulse pressure, 85 mm Hg. The mean systemic resistance units were 0.17 and 0.16 for carotid and tibial arteries respectively on a bird basis and 1.13 and 1.08 respectively per kg body weight0.734.

Immediate effects of cigarette smoking on cardiorespiratory responses to exercise

1985 ◽  
Vol 58 (6) ◽  
pp. 1975-1981 ◽  
Author(s):  
G. L. Hirsch ◽  
D. Y. Sue ◽  
K. Wasserman ◽  
T. E. Robinson ◽  
J. E. Hansen
Keyword(s):  
Gas Exchange ◽  
Cigarette Smoking ◽  
Pulse Pressure ◽  
Minute Ventilation ◽  
Cardiovascular Responses ◽  
Co2 Production ◽  
Blood Levels ◽  
Maximal Aerobic Capacity ◽  
Arterial Blood ◽  
End Tidal

To determine the acute action of cigarette smoking on cardiorespiratory function under stress, the immediate effects of cigarette smoking on the ventilatory, gas exchange, and cardiovascular responses to exercise were studied in nine healthy male subjects. Each subject performed an incremental exercise test to exhaustion on two separate days, one without smoking (control) and one after smoking 3 cigarettes/h for 5 h. The order of the two tests was randomized. Arterial blood gases and pH were measured during rest and all levels of exercise; CO blood levels confirmed the absorption of cigarette smoke. In addition, minute ventilation (VE), end-tidal PCO2 and PO2, O2 uptake (VO2), CO2 production, directly measured blood pressure, electrocardiogram, and heart rate (HR) were recorded every 30 s. The dead space-to-tidal volume ratio (VD/VT), maximal aerobic capacity (VO2max), and anaerobic threshold (AT) were determined from the gas exchange data. Cigarette smoking resulted in a significantly lower VO2max, AT, and VO2/HR (O2 pulse) and a significantly higher HR, pulse-pressure product, and pulse pressure (P less than 0.05) compared with the control. Additionally, a trend toward a higher VD/VT and arterial-end-tidal PCO2 difference was found during exercise after smoking. We conclude that cigarette smoking causes immediate detrimental effects on cardiovascular function during exercise, including tachycardia, increased pulse-pressure product, and impaired O2 delivery. The acute effects on respiratory function were less striking and primarily limited to abnormalities reflecting ventilation-perfusion mismatching.

The Role of SDF-1/CXCR4 in the Procession of Auto-Stem Cell Transplantation of Multiply Myeloma Patients.

Blood ◽  
2006 ◽  
Vol 108 (11) ◽  
pp. 5150-5150
Author(s):  
Caixia Li ◽  
De Pei Wu ◽  
Xue Guang Zhang
Keyword(s):  
Stem Cell ◽  
Plasma Levels ◽  
Peripheral Blood Stem Cell ◽  
Cxcr4 Expression ◽  
Lower Plasma ◽  
Cxcr4 Receptor ◽  
Cd34 Cells ◽  
The Mean ◽  
Poor Mobilizers

Abstract CXCR4, receptor of the chemokine stromal derived factor-1 (SDF-1), is expressed on CD34+ cells, and has been implicated in the process of CD34+ cell migration and homing. We studied the mobilization of CD34/CXCR4 cells and the plasma levels of SDF-1 and sgp130 in 22 patients, 11 acute Leukemia, 5 non-Hodgkin’s lymphoma, and 6 multiply myloma respectably, receiving cyclophosphamide (Cy) and plus G-CSF, or Mitoxantrone(Mit) and Cytarabine plus G-CSF for peripheral blood stem cell (PBSC) mobilization and autotransplantation. We observed lower plasma levels of SDF-1 in PBSCs compared with premobilized PB and bone marrow samples. The average levels of SDF-1 and sgp130 were 24.67±5.58ng/ml and 106.2±16.4ng/ml respectively while the level of SDF-1 as well as sgp130 decreased to 14659±2.11ng/ml(p&lt;0.05)and 58.8±29.1ng/ml(p&lt;0.05) respectively on day when PBSC was collected after mobilization. SDF-1 levels in the apheresis collections of the “good mobilizers” (patients who collected a minimum of 2 × 106 CD34+ cells/kg in one to three PBSC collections) were significantly lower than the apheresis collections of the “poor mobilizers” (&lt;2 × 106 CD34+ cells/kg in the three cycles of PBSC collections; 14.82 ± 7.08 ng/ml versus 27.2 ± 8.13 ng/ml; p&lt;0.01). The mean percentage of CD34+ cells expressing CXCR4 in the apheresis collections was decreased in the PBSC collections compared with premobilization values ranging from 32.09±5.39% to 22.4±5.92%. But the mean CXCR4 expression on CD34+ cells of the good mobilizers was not different from the expression on CD34+ cells of poor mobilizers. Furthermore, the levels of sgp130 closely correlated with SDF-1 levels (r = 0.87; p &lt; 0.001); the plasma level of SDF-1 and expression of CXCR4 on the CD34+ cells were gradually decreased in the PB of patients during the procession of mobilization; low plasma levels of SDF-1 turned out with good mobilization outcome, and the levels of SDF-1 correlated with sgp130, suggesting an association of these cytokines in mobilization of CD34+ cells.

Pharmacokinetics and Arteriovenous Differences in Clevidipine Concentration following a Short- and a Long-term Intravenous Infusion in Healthy Volunteers

2000 ◽  
Vol 92 (4) ◽  
pp. 993-1001 ◽  
Author(s):  
Hans Ericsson ◽  
Ulf Bredberg ◽  
Ulf Eriksson ◽  
Åse Jolin-Mellgård ◽  
Margareta Nordlander ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Steady State ◽  
Healthy Volunteers ◽  
Venous Blood ◽  
Volume Of Distribution ◽  
Pharmacokinetic Parameters ◽  
Blood Levels ◽  
Blood Concentrations ◽  
Arterial Blood ◽  
The Mean

Background Clevidipine is an ultra-short-acting calcium antagonist developed for reduction and control of blood pressure during cardiac surgery. The objectives of the current study were to determine the pharmacokinetics of clevidipine after 20-min and 24-h intravenous infusions, and to determine the relation between the arterial and venous concentrations and the hemodynamic responses to clevidipine in healthy volunteers. Methods Four volunteers received clevidipine for 20 min, and eight subjects were administered clevidipine intravenously for 24 h at two different dose rates. Arterial and venous blood samples were drawn for pharmacokinetic evaluation, and blood pressure and heart rate were recorded. Results A triexponential disposition model described the pharmacokinetics of clevidipine. The mean arterial blood clearance of clevidipine was 0.069l/kg-1/min-1 and the mean volume of distribution at steady state was 0.19 l/kg. The duration of the infusion had negligible effect on the pharmacokinetic parameters, and the context-sensitive half-time for clevidipine, simulated from the mean pharmacokinetic parameters derived after 24 h infusion at the highest dose, was less than 1 min. The arterial blood levels reached steady state within 2 min of the start of infusion and were about twice as high as those in the venous blood at steady state. The peak response preceded the peak venous concentration and was slightly delayed from the peak arterial blood concentration. Conclusion Clevidipine is a high clearance drug with a small volume of distribution, resulting in extremely short half-lives in healthy subjects. The initial rapid increase in the arterial blood concentrations and the short equilibrium time between the blood and the biophase suggest that clevidipine can be rapidly titrated to the desired effect.

THE METABOLISM OF INJECTED PROGESTERONE IN THE EWE

1963 ◽  
Vol 26 (1) ◽  
pp. 65-73 ◽  
Author(s):  
M. G. BRUSH
Keyword(s):  
Plasma Levels ◽  
Blood Levels ◽  
Plasma Progesterone ◽  
The Mean ◽  
Mean Concentration

SUMMARY Plasma levels of progesterone and 20 α-hydroxypregn-4-en-3-one have been studied after intravenous (i.v.) and intramuscular (i.m.) injections of progesterone in sheep. I.v. injected progesterone was removed from the bloodstream very rapidly and it was necessary to give 50 mg. before it was possible to detect progesterone at times up to 10 min. after the injection. With 100 mg. amounts of progesterone injected i.v. the mean concentration in samples taken up to 10 min. after the injection was 34·7 μg./100 ml. plasma (range 4–110 μg./100 ml. in 9 samples), but after 1 hr. the mean level was 2·2 μg./100 ml. plasma (range 0–10 μg./100 ml. in 10 samples). The concentrations of 20 α-hydroxypregn-4-en-3-one were usually, but not always, less than those of progesterone. When progesterone was given by i.m. injection it was not possible to establish detectable blood levels. The effect of the injection vehicle was also studied for each injection route. Some new modifications of Short's method (1958) for the determination of plasma progesterone are described and discussed.

Neuroprotection for Spine Surgery

2017 ◽  
Author(s):  
Jess W. Brallier ◽  
Jonathan S. Gal
Keyword(s):  
Evoked Potentials ◽  
Spine Surgery ◽  
Motor Evoked Potentials ◽  
Neurologic Injury ◽  
Arterial Blood ◽  
Increased Risk ◽  
Physiologic Parameter ◽  
The Common ◽  
Transcranial Motor Evoked Potentials

Perioperative neurologic injury related to spine surgery, albeit rare, can result in devastating functional loss. As the number of spine operations has increased, so has the need for strategies designed to avoid and protect against such injury. This chapter reviews the common etiologies of neurologic deficits secondary to spine surgery and the factors that place patients at increased risk for developing these complications. The use of intraoperative neuromonitoring, including somatosensory evoked potentials (SSEPs), electromyography (EMG), and transcranial motor evoked potentials (TcMEPs), to detect surgical trespass of neuronal elements is also reviewed. The authors also summarize the role of physiologic parameter optimization, including mean arterial blood pressure and body temperature, and pharmacologic interventions, should an injury occur. Current practice guidelines for preventing and managing perioperative neurologic injury are described.

Interplay among carotid sinus, cardiopulmonary, and carotid body reflexes in dogs

1976 ◽  
Vol 230 (1) ◽  
pp. 19-24 ◽  
Author(s):  
G Mancia ◽  
JT Shepherd ◽  
DE Donald
Keyword(s):  
Blood Pressure ◽  
Arterial Blood Pressure ◽  
Vascular Resistance ◽  
Carotid Body ◽  
Carotid Sinus ◽  
Dominant Role ◽  
Arterial Blood ◽  
Carotid Bodies ◽  
Sinus Pressure

Interactions among vascular reflexes evoked from carotid sinuses, carotid bodies, and cardiopulmonary region were examined in anesthetized, atropinized, and respired dogs with aortic nerves cut. The carotid sinuses were perfused at 220, 150, and 40-50 mmHg; the chemoreceptors were stimulated by perfusion with hypoxic hypercapnic blood. Cardiopulmonary vasomotor inhibition was interrupted by vagal cold block. Measurements were made of arterial blood pressure and of kidney and hindlimb vascular resistance. At sinus pressures less than 170-160 mmHg, cardiopulmonary vasomotor inhibition increased with increase in blood volume. At high sinus pressure, interruption of this augmented cardiopulmonary inhibition was as ineffective in changing vascular resistance as interruption of the lesser inhibition present during normovolemia. Chemoreceptor stimulation increased the response to vagal block at intermediate but not at high or low sinus pressure. The studies demonstrate the dominant role of the carotid sinus reflex when the three systems interact and the ineffectiveness of chemoreceptor stimulation when carotid or cardiopulmonary inhibition is maximal.

THE CARDIAC OUTPUT AND CAROTID AND TIBIAL BLOOD PRESSURE OF THE TURKEY

1963 ◽  
Vol 41 (1) ◽  
pp. 2337-2341 ◽  
Author(s):  
Elwood W. Speckmann ◽  
Robert K. Ringer
Keyword(s):  
Body Weight ◽  
Cardiac Output ◽  
Pulse Pressure ◽  
Mature Male ◽  
Systemic Resistance ◽  
Hemodynamic Parameters ◽  
Radioactive Phosphorus ◽  
Arterial Blood ◽  
Tibial Arteries ◽  
The Mean

The cardiac output of untreated mature male Broad Breasted Bronze (BBB) turkeys was determined by an isotope dilution technique using radioactive phosphorus (P32). A Geiger–Mueller tube was connected to a rate meter which in turn was connected to a moving graph to continuously record the indicator concentration, thus obtaining the initial dilution curve. Posterior tibial and common carotid arterial blood pressures were measured directly and were recorded simultaneously with the cardiac output determinations by means of two strain gauges connected to a recording polygraph.From the cardiovascular measurements systemic resistance was calculated. The mean cardiac output of the mature male BBB turkey was 231 ml per kg body weight0.734 per minute. The mean carotid hemodynamic parameters were: systolic BP, 302 mm Hg; diastolic BP, 204 mm Hg; and pulse pressure, 98 mm Hg. Heart rate was 149 beats per minute. The mean tibial hemodynamic parameters were; systolic BP, 286 mm Hg; diastolic BP, 200 mm Hg; and pulse pressure, 85 mm Hg. The mean systemic resistance units were 0.17 and 0.16 for carotid and tibial arteries respectively on a bird basis and 1.13 and 1.08 respectively per kg body weight0.734.

Respiratory sensitivity to carbon dioxide in cross-circulated dogs

1962 ◽  
Vol 202 (5) ◽  
pp. 1024-1028 ◽  
Author(s):  
Frederick F. Kao ◽  
Remedios G. Suntay ◽  
William K. Li
Keyword(s):  
Carbon Dioxide ◽  
Carotid Arteries ◽  
Ventilatory Response ◽  
Sensitivity Coefficient ◽  
Vertebral Arteries ◽  
Arterial Blood ◽  
The Common ◽  
Respiratory Centers ◽  
Common Carotid Arteries ◽  
Respiratory Sensitivity

The effect of CO2 on ventilation was studied in cross-circulated dogs. In these experiments the recipient dog's head was perfused exclusively by arterial blood from the donor dog through anastomoses of the common carotid arteries of the donor to the vertebral arteries of the recipient. The carotid arteries of the recipient dog, as well as its muscles in the neck, were tied. The injection of lipiodol and latex did not reveal leakage from the recipient's head to its body or vice versa. Ventilation and arterial Pco2 of both dogs were determined before, during, and after the inhalation of carbon dioxide of 3, 5, and 7% with 20% oxygen and balance nitrogen by the donor for 20 min or more. The sensitivity of the respiratory centers of both dogs to Pco2 was similar, as indicated by the regression lines relating ventilation in both dogs as a function of arterial Pco2 of the donor dog only. The blood of the recipient's body was hypocapnic when its head was receiving hypercapnic blood. The sensitivity coefficient in both dogs was similar to that of decerebrate dogs during CO2 inhalation. It is inferred that the central CO2 chemoreceptors can account for all the ventilatory response to CO2 inhalation.

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