Dose-Response Curve and Time Course of the Antihypertensive Effect of SKF 92 657, a β-Receptor-Blocking and Vasodilating Compound

1980 ◽  
Vol 59 (s6) ◽  
pp. 461s-463s ◽  
Author(s):  
G. Leonetti ◽  
Laura Terzoli ◽  
Carla Sala ◽  
C. Bianchini ◽  
A. Zanchetti
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Response Curve ◽  
Time Course ◽  
Antihypertensive Effect ◽  
Blood Pressure Reduction ◽  
Dynamic Exercise ◽  
Β Receptor ◽  
Oral Doses ◽  
Uniform Reduction

1. The antihypertensive effect of the new drug, SKF 92 657, a hydrazinopyridazine derivative, possessing both β-adrenoreceptor-blocking and vasodilating properties, was investigated in essential hypertension. 2. Single oral doses of 1.0 or 2.0 mg/kg did not produce any consistent decrease in blood pressure; 4.0 mg/kg was the threshold dose for a mild but not significant blood pressure reduction, whereas 8.0 mg/kg caused a significant and marked blood pressure decrease without clinically relevant changes in heart rate. 3. Continued administration of the drug for 7 days induced a significant and uniform reduction in blood pressure without tachycardia. The increase in systolic blood pressure and in heart rate caused by dynamic exercise was left unaffected by the drug.

Effects of Prizidilol (SKF 92657) on Blood Pressure, Haemodynamics, Sympathetic Nervous System Activity and Plasma Volume in Essential Hypertension

1981 ◽  
Vol 61 (s7) ◽  
pp. 465s-468s ◽  
Author(s):  
R. Fariello ◽  
C. L. Alicandri ◽  
E. Agabiti-Rosei ◽  
G. Romanelli ◽  
M. Castellano ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Plasma Volume ◽  
Antihypertensive Effect ◽  
Blood Pressure Reduction ◽  
Cardiac Performance ◽  
Plasma Aldosterone ◽  
Nervous System Activity ◽  
Peripheral Vasodilatation ◽  
Noradrenaline And Adrenaline

1. The antihypertensive effect of 4 weeks' treatment with prizidilol (SKF 92657) (mean dosage 520 mg once or twice daily) was studied in ten essential hypertensive patients. 2. Both systolic and diastolic blood pressure were significantly reduced in all cases. Supine heart rate did not change, and in the erect position heart rate was significantly lowered. 3. Blood pressure reduction was due to peripheral vasodilatation, as the cardiac index increased after 4 weeks of prizidilol treatment. 4. After prizidilol plasma noradrenaline and adrenaline increased significantly, and PRA and plasma aldosterone were reduced. Although plasma volume increased, body weight did not change. 5. Cardiac performance, as evaluated by the PEP/LVET ratio, improved after treatment with prizidilol.

Effects of hydralazine on blood pressure, pressor mechanisms, and cardiac hypertrophy in two-kidney, one-clip hypertensive rats

1986 ◽  
Vol 64 (12) ◽  
pp. 1528-1534 ◽  
Author(s):  
James Tsoporis ◽  
Frans H. H. Leenen
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Time Course ◽  
Antihypertensive Effect ◽  
Plasma Catecholamines ◽  
Left Ventricular ◽  
Prolonged Treatment ◽  
Internal Diameter ◽  
Hypertensive Rats ◽  
Blood Volumes

In 2-kidney, 1-clip hypertensive rats, the time course of changes in blood pressure (BP), heart rate, activity of the sympathetic nervous system and the renin–angiotensin system, plasma and blood volumes, left ventricular (LV) and right ventricular (RV) weight, and LV dimensions were evaluated during treatment with hydralazine 80 and 120 mg/L drinking water for 2 days or 1, 2, 3, 5, and 8 weeks. Hydralazine induced initially a clear antihypertensive effect (mean BP from 170–180 down to 135–145 mmHg (1 mmHg = 133.32 Pa)), subsequently tolerance developed. Heart rate, plasma catecholamines, and the blood pressure response to hexamethonium were not affected by treatment. Significant increases in plasma renin activity occurred during the initial 1–3 weeks of treatment. Plasma and blood volumes showed only small increases with prolonged treatment. RV weight and LV internal diameter showed significant increases at 3, 5, and 8 weeks of treatment, LV weight at 5 and 8 weeks. LV wall thickness did not change significantly. Thus, treatment with the arterial vasodilator hydralazine causes both RV hypertrophy and eccentric LV hypertrophy. Intravascular volume expansion, associated possibly with redistribution of blood volume to the central compartment, may play a major role in these cardiac effects. Increased renin release but not a generalized increase in sympathetic tone may play a role in the development of tolerance to the antihypertensive effect.

Ruta montana evokes antihypertensive activity through increase of prosta-glandins release in L-NAME-induced hypertensive rats

2020 ◽  
Vol 20 ◽  
Author(s):  
El-Ouady Fadwa ◽  
Mohamed Eddouks
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Aqueous Extract ◽  
Antihypertensive Effect ◽  
Antihypertensive Activity ◽  
Computer Assisted ◽  
Hypertensive Rats ◽  
Vasorelaxant Effect ◽  
Vasorelaxant Activity ◽  
Ruta Montana

Aims: The aim of the study was to investigate experimentally the antihypertensive effect of Ruta Montana. Background: Ruta montana L. is traditionally used in Moroccan herbal medicine to treat hypertension. This study aimed to evaluate experimentally the hypotensive and vasoactive properties of this plant. Objective: The objective of the study was to evaluate the effect of the aqueous extract of Ruta Montana on blood pressure parameters in LNAME-induced hypertensive rats and to determine the vasorelaxant activity of this aqueous extract. Methods: The antihypertensive effect of the aqueous extract obtained from Ruta montana aerial parts (RMAPAE) (200 mg/kg) was evaluated in normal and anesthetized hypertensive rats. Blood pressure parameters (systolic blood pressure (SBP), mean blood pressure (MBP) and diastolic blood pressure (DBP)) and heart rate were measured using a tail-cuff and a computer-assisted monitoring device. The acute and chronic effect of RMAPAE was recorded during 6 hours for the acute experiment and during 7 days for the sub-chronic test. In the other set, the vasorelaxant effect of RMAPAE on the contractile response was undertaken in isolated thoracic aorta. Results: The results indicated that RMAPAE extract significantly decreased SBP, MBP, DBP and heart rate in L-NAMEinduced hypertensive rats. Furthermore, RMAPAE was demonstrated to induce a dose dependent relaxation in the aorta precontracted with Epinephrine or KCl. More interestingly, this vasorelaxant activity of RMAPAE seems to be probably mediated through the prostaglandins pathway. Conclusion: The present study illustrates the beneficial action of Ruta montana on hypertension and supports then its use as an antihypertensive agent.

A Comparison of the Acute Haemodynamic Effects of Propranolol and Pindolol at Rest and during Supine Exercise in Man

1980 ◽  
Vol 59 (s6) ◽  
pp. 465s-468s ◽  
Author(s):  
T. L. Svendsen ◽  
J. E. Carlsen ◽  
O. Hartling ◽  
A. McNair ◽  
J. Trap-Jensen
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Cardiac Output ◽  
Pulmonary Artery ◽  
Pulmonary Artery Pressure ◽  
Response Curves ◽  
Receptor Blocking ◽  
Artery Pressure ◽  
Arterial Blood ◽  
Β Receptor

1. Dose-response curves for heart rate, cardiac output, arterial blood pressure and pulmonary artery pressure were obtained in 16 male patients after intravenous administration of three increasing doses of pindolol, propranolol or placebo. All patients had an uncomplicated acute myocardial infarction 6–8 months earlier. 2. The dose-response curves were obtained at rest and during repeated bouts of supine bicycle exercise. The cumulative dose amounted to 0.024 mg/kg body weight for pindolol and to 0.192 mg/kg body weight for propranolol. 3. At rest propranolol significantly reduced heart rate and cardiac output by 12% and 15% respectively. Arterial mean blood pressure was reduced by 9.2 mmHg. Mean pulmonary artery pressure increased significantly by 2 mmHg. Statistically significant changes in these variables were not seen after pindolol or placebo. 4. During exercise pindolol and propranolol both reduced cardiac output, heart rate and arterial blood pressure to the same extent. After propranolol mean pulmonary artery pressure was increased significantly by 3.6 mmHg. Pindolol and placebo did not change pulmonary artery pressure significantly. 5. The study suggests that pindolol may offer haemodynamic advantages over β-receptor-blocking agents without intrinsic sympathomimetic activity during low activity of the sympathetic nervous system, and may be preferable in situations where the β-receptor-blocking effect is required only during physical or psychic stress.

Antihypertensive Property and Renal Protection by Shichimotsu-koka-to Extract in Salt-induced Hypertension in Dahl Strain Rats

1994 ◽  
Vol 22 (01) ◽  
pp. 51-62 ◽  
Author(s):  
Nobuhito Hiwara ◽  
Yoshio Uehara ◽  
Satoru Takada ◽  
Yukari Kawabata ◽  
Nobuko Ohshima ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Renal Function ◽  
Aortic Wall ◽  
Antihypertensive Effect ◽  
Blood Pressure Reduction ◽  
Glomerular Sclerosis ◽  
Pressure Reduction ◽  
Renal Protection ◽  
Induced Hypertension ◽  
Sclerotic Lesions

We determined whether or not the kampo formula, Shichimotsu-koka-to extract, attenuates the development of salt-induced hypertension and provides renal protection against hypertensive injury in Dahl salt-sensitive (Dahl S) rats. A six-week treatment using this formula dose-dependently decreased the systolic blood pressure in Dahl S rats fed a high-salt (2% NaCl) diet. This blood pressure reduction was associated with a decrease in the thickness of the aortic wall. Renal function was not altered with this treatment; however, glomerular sclerotic lesions in the kidney were significantly attenuated. Neither arterial nor tubular lesions were affected. These data suggest that Shichimotsu-koka-to extract exhibits an antihypertensive effect which is associated with partial resolution of glomerular sclerosis in the kidney.

Measurement of sympathetic nerve activity in the unanesthetized rat

1989 ◽  
Vol 67 (1) ◽  
pp. 250-255 ◽  
Author(s):  
J. P. Fluckiger ◽  
G. Gremaud ◽  
B. Waeber ◽  
A. Kulik ◽  
A. Ichino ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Arterial Pressure ◽  
Sympathetic Nerve ◽  
Sympathetic Nerve Activity ◽  
Blood Pressure Reduction ◽  
Response Curves ◽  
Nerve Activity ◽  
Dose Dependent

A new system was developed in our laboratory to continuously monitor intra-arterial pressure, heart rate, and sympathetic nerve activity in unanesthetized rats. The animals were prepared 24 h before the start of the experiments. Sympathoneural traffic was measured at the level of splanchnic nerve. The amplitude of the spikes recorded at this level was utilized to express sympathetic nerve activity. The amplitude of the residual electroneurogram signal present 30 min after the rats were killed was 32 +/- 2 mV (mean +/- SE; n = 11). For analysis, these background values were subtracted from values determined in vivo. The nerve we studied contains postganglionic fibers, since electrical activity decreased in response to ganglionic blockade with pentolinium (1.25 mg/min iv for 4 min). The amplitude of spikes fell by 43 +/- 4% (n = 4). Sympathetic nerve activity was highly reproducible at a 24-h interval (104 +/- 26 vs. 111 +/- 27 mV for the amplitude of spikes; n = 11). Dose-response curves to the alpha 1-stimulant methoxamine and to bradykinin were established in four rats. The increase in blood pressure induced by methoxamine caused a dose-dependent fall in sympathetic nerve activity, whereas the blood pressure reduction resulting from bradykinin was associated with a dose-dependent activation of sympathetic drive. These data therefore indicate that it is possible with out system to accurately measure sympathetic nerve activity in the awake rat, together with intra-arterial pressure and heart rate.

Participation of central alpha-receptors on hemodynamic response to E. coli endotoxin

1984 ◽  
Vol 247 (4) ◽  
pp. R655-R662
Author(s):  
S. Koyama
Keyword(s):  
Blood Pressure ◽  
Central Nervous System ◽  
Heart Rate ◽  
Time Course ◽  
Hypotensive Effect ◽  
Control Group ◽  
E Coli ◽  
Alpha Receptors ◽  
Anesthetized Dogs ◽  
The Central Nervous System

The time course of changes in mean blood pressure (MBP), heart rate (HR), and renal blood flow (RBF) in a control group of anesthetized dogs given only endotoxin (1 mg/kg iv) was compared with groups pretreated with alpha-antagonists either intravenously or intracisternally (ic). The decreases in MBP and RBF in the control group were abolished by intracisternal prazosin (0.1 mg/kg ic). MBP response to endotoxin after intravenous prazosin did not differ from that of the control group; however, the endotoxin-induced decrease in RBF after intravenous prazosin was significantly greater than that in the control group. HR responses to endotoxin were not altered by either intracisternal or intravenous prazosin. MBP and RBF responses to endotoxin after intravenous or intracisternal yohimbine (0.5 mg/kg iv or ic) did not differ from the control responses. However, significant differences occurred in the time course of changes in HR only when yohimbine was administered intracisternally. These observations suggest that the hypotensive effect and reduction of RBF due to endotoxin may be mediated by alpha 1-adrenoceptors at least in the central nervous system and that of HR response may be mediated alpha 2-adrenoceptors.

Effects of caffeine on blood pressure, heart rate, and forearm blood flow during dynamic leg exercise

1998 ◽  
Vol 85 (1) ◽  
pp. 154-159 ◽  
Author(s):  
Jason W. Daniels ◽  
Paul A. Molé ◽  
James D. Shaffrath ◽  
Charles L. Stebbins
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Blood Flow ◽  
Systolic Blood Pressure ◽  
Skin Temperature ◽  
Rectal Temperature ◽  
Forearm Blood Flow ◽  
Dynamic Exercise ◽  
Ang Ii ◽  
Leg Exercise

This study examined the acute effects of caffeine on the cardiovascular system during dynamic leg exercise. Ten trained, caffeine-naive cyclists (7 women and 3 men) were studied at rest and during bicycle ergometry before and after the ingestion of 6 mg/kg caffeine or 6 mg/kg fructose (placebo) with 250 ml of water. After consumption of caffeine or placebo, subjects either rested for 100 min (rest protocol) or rested for 45 min followed by 55 min of cycle ergometry at 65% of maximal oxygen consumption (exercise protocol). Measurement of mean arterial pressure (MAP), forearm blood flow (FBF), heart rate, skin temperature, and rectal temperature and calculation of forearm vascular conductance (FVC) were made at baseline and at 20-min intervals. Plasma ANG II was measured at baseline and at 60 min postingestion in the two exercise protocols. Before exercise, caffeine increased both systolic blood pressure (17%) and MAP (11%) without affecting FBF or FVC. During dynamic exercise, caffeine attenuated the increase in FBF (53%) and FVC (50%) and accentuated exercise-induced increases in ANG II (44%). Systolic blood pressure and MAP were also higher during exercise plus caffeine; however, these increases were secondary to the effects of caffeine on resting blood pressure. No significant differences were observed in heart rate, skin temperature, or rectal temperature. These findings indicate that caffeine can alter the cardiovascular response to dynamic exercise in a manner that may modify regional blood flow and conductance.

scholarly journals TIME COURSE OF BLOOD PRESSURE REDUCTION AFTER RENAL DENERVATION

2013 ◽  
Vol 61 (10) ◽  
pp. E1378
Author(s):  
Willemien Verloop ◽  
Eva E. Vink ◽  
Peter J. Blankestijn ◽  
Evert-Jan Vonken ◽  
Pieter A. Doevendans ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Renal Denervation ◽  
Time Course ◽  
Blood Pressure Reduction ◽  
Pressure Reduction
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