P504 HEMODYNAMIC RESPONSE TO NON-SELECTIVE BETA BLOCKERS DESPITE LACK OF EFFECTS ON HEART RATE AND SYSTEMIC BLOOD PRESSURE

2014 ◽  
Vol 60 (1) ◽  
pp. S237
Author(s):  
S. Bota ◽  
M. Mandorfer ◽  
P. Schwabl ◽  
P. Salzl ◽  
A. Ferlitsch ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Beta Blockers ◽  
Systemic Blood Pressure ◽  
Hemodynamic Response ◽  
Systemic Blood

scholarly journals Changes in Respiratory Rate, Blood Pressure and Heart Rate Variability in Rabbits during Orthostasis

2006 ◽  
Vol 75 (1) ◽  
pp. 3-12 ◽  
Author(s):  
J. Mokrý ◽  
T. Remeňová ◽  
K. Javorka
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Heart Rate Variability ◽  
Respiratory Rate ◽  
Supine Position ◽  
Spectral Power ◽  
Systemic Blood Pressure ◽  
Microcomputer System ◽  
Systemic Blood ◽  
Frequency Bands

The purpose of the study was to evaluate the changes of respiratory rate, systemic blood pressure and heart rate variability parameters (HRV) during orthostasis in anaesthetized rabbits. Furthermore, these changes were influenced by affecting the renin-angiotensin-aldosterone (RAA) system and autonomic nervous system (ANS) to study the mechanisms participating in activity of spectral frequency bands of HRV in rabbits. Ten adult rabbits (Chinchilla) were anaesthetized by ketamine and flunitrazepam. The systemic blood pressure, tidal volume and respiratory rate were measured. HRV was evaluated by microcomputer system VariaPulse TF3E. The R-R intervals were derived from the electrocardiogram signal from subcutaneous needle electrodes. The evaluation of HRV in very low (VLF; 0.01-0.05 Hz), low (LF; 0.05-0.15 Hz) and high frequency bands (HF; 0.15-2.0 Hz) was made and parameters of frequency and time analysis were calculated. The measurements were made in horizontal (supine) position, in orthostasis (the angle of 60 °) and again in supine position before and after enalapril (0.5 mg/kg b.w.), metipranolol (0.2 mg/kg b.w.), and after subsequent bilateral cervical vagotomy. The orthostasis in anaesthetized rabbits is accompanied by depression of respiratory rate reversed only by vagotomy. Furthermore, decrease of systemic blood pressure, unchanged heart rate and increased characteristics of heart rate variability were found, with predominant increase of spectral power in LF and VLF bands. This elevation can be eliminated only by complete blockade of ANS. Although the participation of ANS or RAA system in modification of individual HRV frequency bands is not as specific as in humans, we confirmed the participation of RAA system in determination of the VLF band.

Neural mechanism underlying basilar arterial constriction by intracisternal L-NNA in anesthetized dogs

1993 ◽  
Vol 265 (1) ◽  
pp. H103-H107 ◽  
Author(s):  
N. Toda ◽  
K. Ayajiki ◽  
T. Okamura
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Cerebral Arteries ◽  
Neural Mechanism ◽  
Systemic Blood Pressure ◽  
Systemic Blood ◽  
Anesthetized Dogs ◽  
Arterial Constriction ◽  
Synthase Inhibitor

Basilar arterial diameters were angiographically measured in anesthetized dogs in which systemic blood pressure and heart rate were also monitored. Injections of NG-nitro-L-arginine (L-NNA), a NO synthase inhibitor, into the cisterna magna produced a significant, persistent decrease in arterial diameter, the effect being reversed by intracisternal injections of L-arginine. The vasoconstrictor effect of L-NNA was diminished in dogs treated with hexamethonium. On the other hand, treatment with phentolamine in a dose sufficient to lower blood pressure to a level similar to that attained with hexamethonium did not inhibit, but rather potentiated, the effect of intracisternal L-NNA. Nicotine injected into the vertebral artery significantly dilated the basilar artery. The effect was abolished by treatment with L-NNA applied intracisternally, the inhibition being reversed by the addition of L-arginine. Systemic blood pressure and heart rate were not altered by intracisternally applied L-NNA and L-arginine. These findings support the hypothesis that basilar arterial constriction caused by intracisternal L-NNA is associated with a suppression of NO synthesis in nitroxidergic nerves innervating the cerebroarterial wall rather than an elimination of basal release of NO from the endothelium. Functional importance of nitroxidergic vasodilator innervation in cerebral arteries in vivo is thus clarified.

Baroreceptor influence on postural changes in blood pressure and carotid blood flow

1963 ◽  
Vol 205 (2) ◽  
pp. 360-364 ◽  
Author(s):  
Francis L. Abel ◽  
John H. Pierce ◽  
Warren G. Guntheroth
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Carotid Sinus ◽  
Systemic Blood Pressure ◽  
Systemic Blood ◽  
Carotid Blood Flow ◽  
Postural Changes ◽  
Nembutal Anesthesia

The effects of 30° head-down and head-up tilting on mean systemic blood pressure, carotid blood flow, and heart rate were studied in 16 dogs under morphine and Nembutal anesthesia. The tilting procedure was further repeated after denervation of the carotid sinus and aortic arch baroreceptors and after administration of a dihydrogenated ergot alkaloid mixture (Hydergine). The results indicate that the drop in pressure in the head-down position is primarily due to baroreceptor activity and that the baroreceptors are necessary for compensatory vasoconstriction on head-up tilting. Carotid blood flow decreased in both tilted positions in the control animals; the possible relationship to cerebral blood flow is discussed.

scholarly journals PROGNOSTIC VALUE OF HEART RATE AND SYSTEMIC BLOOD PRESSURE IN PULMONARY ARTERIAL HYPERTENSION

2010 ◽  
Vol 55 (10) ◽  
pp. A154.E1443
Author(s):  
Malcolm M. Bersohn ◽  
Shelley Shapiro ◽  
Michelle P. Turner ◽  
Glenna Traiger ◽  
Adaani E. Frost
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Pulmonary Arterial Hypertension ◽  
Arterial Hypertension ◽  
Prognostic Value ◽  
Systemic Blood Pressure ◽  
Systemic Blood ◽  
Pulmonary Arterial

Influence of Sympatholytic Drugs on the Cardiovascular Response to Isometric Exercise

1981 ◽  
Vol 60 (2) ◽  
pp. 139-143 ◽  
Author(s):  
S. J. Watt ◽  
R. D. Thomas ◽  
P. W. Belfield ◽  
P. W. Goldstraw ◽  
S. H. Taylor
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Healthy Subjects ◽  
Cardiovascular Response ◽  
Pressor Response ◽  
Isometric Exercise ◽  
Systemic Blood Pressure ◽  
Isometric Handgrip ◽  
Systemic Blood ◽  
Oral Doses

1. The effects of single oral doses of various sympatholytic drugs on the heart rate and blood pressure increases during isometric handgrip contraction were studied in six healthy subjects. 2. Bethanidine reduced both the systolic and diastolic increases in pressure. Clonidine reduced the systolic but not the diastolic increase. Oxprenolol alone or in combination with phentolamine or phenyoxybenzamine failed to influence the pressor response. 3. The increase in systemic blood pressure associated with sustained contraction of voluntary muscle appears to be relatively resistant to acute sympathetic adrenoreceptor blockade in man.

Effects of droperidol on systemic blood pressure, heart rate and renal nerve activity in anesthetized rabbits

1992 ◽  
Vol 37 (1) ◽  
pp. 70
Author(s):  
Masayuki Aibiki ◽  
Shinji Ogura ◽  
Yoichi Shirakawa ◽  
Keisuke Honda ◽  
Osamu Umegaki ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Systemic Blood Pressure ◽  
Systemic Blood ◽  
Nerve Activity ◽  
Renal Nerve ◽  
Renal Nerve Activity

Heart Rate-Systemic Blood Pressure Relationship in Dogs During Halothane Anesthesia

1980 ◽  
Vol 24 (3) ◽  
pp. 181-186 ◽  
Author(s):  
P. L. Wilkinson ◽  
D. F. Stowe ◽  
S. A. Glantz ◽  
J. V. Tyberg
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Systemic Blood Pressure ◽  
Halothane Anesthesia ◽  
Systemic Blood

Autonomic cardiovascular control during submergence and emergence in bullfrogs

1979 ◽  
Vol 237 (3) ◽  
pp. R210-R216
Author(s):  
R. S. Lillo
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Vagal Tone ◽  
Systemic Blood Pressure ◽  
Vagal Activity ◽  
Adrenergic Blockade ◽  
Systemic Blood ◽  
Heart Rates ◽  
Heart Rate Decrease ◽  
Sympathetic Influence

Unanesthetized bullfrogs were involuntarily submerged for 25 min in air-saturated water at 21 degrees C. Significant bradycardia was observed while systemic blood pressure was maintained or slightly elevated. Upon emergence, heart rates immediately returned to presubmergence levels or higher. Similar responses were observed in frogs allowed to make voluntary dives in an experimental tank. Heart rates of vagal-blocked (atropine) frogs did not change during submergence or emergence. beta-Adrenergic blockade (propranolol) had little effect on the magnitude of heart rate decrease during submergence or its increase upon emergence. After alpha-adrenergic blockade (phentolamine), frogs developed diving bradycardia while undergoing a fall in systemic blood pressure. It is concluded that, in bullfrogs, 1) bradycardia during submergence is entirely due to increased vagal activity, 2) the immediate cardiac rate increase upon emergence apparently results from a decrease in vagal tone; and 3) there appears to be no substantial reciprocal sympathetic influence on heart rate during alterations in vagal tone.

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