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Query: UMLS:C0020538 (hypertension)
 170,190 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

While there is general agreement on the natural history, pathology, and pathophysiology of hypertension, there continues to be controversy over the selection of specific antihypertensive agents. All antihypertensive agents will, by definition, lower blood pressure, and factors beyond side effects and other difficulties associated with therapy form the basis of selecting specific agents. One of these factors is the effect of a given drug on core organ function. Propranolol was the first beta-adrenoceptor-blocking agent introduced for the treatment of hypertension. Initiation of therapy with propranolol may result in a decline in blood pressure more at the expense of cardiac function due to a concomitant rise in total peripheral resistance. Furthermore, propranolol may result in a decline in both glomerular filtration rate (GFR) and renal blood flow (RBF). In contrast, cardioselective beta-blockers or those with intrinsic sympathomimetic activity may not adversely affect renal function. It had been predicted that nadolol, a noncardioselective beta-blocker without intrinsic sympathomimetic activity, should result in decreased renal function. In contrast, observations demonstrated a preservation or improvement in both RBF and GFR, suggesting the presence of an alternative effective mechanism. Recent additions to the beta-adrenolytic group of antihypertensive agents include drugs with concurrent beta-blockade and vasodilation. This vasodilatation may be achieved through agonist properties resulting in lesser increases in vasomotor tone and smaller, if any, decreases in cardiac output. Alternatively, vasodilation may be achieved by concomitant alpha-adrenoceptor blockade, such as with labetalol. This agent preserves GFR and RBF during therapy of hypertension, in patients with normal as well as diminished renal function and hypertension.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Beta-blockers and hypertension. 256 44

The metabolic effects of celiprolol, a new beta-adrenoceptor blocking agent with intrinsic sympathomimetic activity and alpha 2-blocking properties, were evaluated in a series of patients with hypertension, both with and without hyperlipidemia. Propranolol was tested as the reference drug in a randomized double-blind trial. Of the 35 patients of both sexes who completed the study, 17 were hyperlipidemic (low-density lipoprotein cholesterol greater than or equal to 170 mg/dl) and 18 were normolipidemic. Both drugs exerted a similar hypotensive effect after gradual dose adjustment; however, propranolol reduced heart rate to a higher extent (-20.5%) than celiprolol (-7.7%). Propranolol determined a significant rise of total and very low-density lipoprotein (VLDL) associated triglyceridemia, whereas high-density lipoprotein cholesterol (HDL cholesterol) levels and the total cholesterol/HDL cholesterol ratios were significantly depressed, particularly in hyperlipidemic patients. Celiprolol, in contrast, slightly decreased triglyceridemia (significantly in the hyperlipidemic group at week 12) and caused a 5% increase of the HDL cholesterol levels. The total cholesterol/HDL cholesterol ratio was reduced by celiprolol at week 16 in both hyperlipidemic and normolipidemic patients. The effects of the two beta-adrenoceptor blockers on HDL cholesterol and triglyceride levels differed significantly after 12 and 16 weeks of treatment, which confirm the divergent metabolic effects of the two agents.
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PMID:Lipid effects of celiprolol, a new cardioselective beta-blocker, versus propranolol. 256 18

The effects of rilmenidine [(N-dicyclopropylmethyl) amino-2-oxazoline; S 3341], an alpha 2 agonist, on the hypertensive rat heart have been compared with those of propranolol, using a model of deoxycorticosterone acetate (DOCA)-salt hypertension. One week after nephrectomy and initial treatment with DOCA-salt, which was continued for an additional 7 weeks, the two drugs were added to the rats drinking water at a concentration of 10 mg/kg per day for rilmenidine and 15 mg/kg per day for propranolol. Both drugs had a slight and similarly significant antihypertensive effect at their respective concentrations [systolic blood pressure in controls, 141 +/- 15 mmHg (n = 20); after DOCA-salt, 209 +/- 22 mmHg (n = 24); after propranolol, 182 +/- 19 mmHg (n = 20, P less than 0.01); after rilmenidine, 192 +/- 15 mmHg (n = 19, P less than 0.05)]. They also lowered the systolic blood pressure x frequency product (P less than 0.001). Propranolol, but not rilmenidine, significantly reduced the left ventricular weight: body weight ratio [in controls, 2.00 +/- 0.2 mg/g; after DOCA-salt, 3.04 +/- 0.5 mg/g; after propranolol, 2.67 +/- 0.4 mg/g (P less than 0.05); after rilmenidine, 3.13 +/- 0.6 mg/g (P = NS)]. However, both propranolol and rilmenidine reduced left ventricular weight [in controls, 676 +/- 57 mg; after DOCA-salt, 827 +/- 114 mg; after propranolol, 732 +/- 108 mg (P less than 0.01); after rilmenidine, 760 +/- 100 mg (P less than 0.05)].(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Remodelling of the heart in DOCA-salt hypertensive rats by propranolol and by an alpha-2 agonist, rilmenidine. 257 30

The effects of chronic oral administration of bopindolol (twice daily for 12 weeks beginning at 5 weeks of age) on serum lipoprotein concentrations, blood pressure and heart rate, were studied in spontaneously hypertensive rats. They were compared with those of two other beta-blockers. Bopindolol and propranolol (15 mg/kg) attenuated the increase in heart rate. Pindolol produced a similar, gradual change in heart rate, but only after the 6th week of treatment. Propranolol and bopindolol attenuated the development of hypertension, whereas pindolol showed no such effect. Pindolol and bopindolol produced a significant increase in high-density lipoprotein cholesterol concentration, but did not produce an increase in serum creatine phosphokinase activity. Administration of these drugs in an acute regimen at 10 weeks of age, provoked changes in blood pressure and heart rate, reflecting partial agonist activities of varying degree, in agreement with the results obtained in chronic experiments with regard to serum lipoprotein concentrations. Pindolol (5 mg/kg) provoked a larger decrease of blood pressure without decrease of heart rate, while the decrease of blood pressure after bopindolol (5 and 15 mg/kg) was associated with a decrease of heart rate. It was concluded that bopindolol is a beta-adrenergic blocking agent with a mild partial agonist activity and devoid of adverse effects on lipid metabolism.
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PMID:Effects of chronic oral administration of a new beta-blocker, bopindolol, on serum lipoprotein concentrations and blood pressure of spontaneously hypertensive rats. 257 91

Dilevalol (SCH 19927) is a potent, long-acting, nonselective beta-blocker with marked vasodilator actions. Unlike classical beta-blockers, dilevalol promptly lowers blood pressure and vascular resistance in animal models of hypertension. The present studies address the peripheral vascular effects of dilevalol and explore the role of beta-receptor agonism in the acute vasodilator and antihypertensive effects of the compound. In the denervated dog hindlimb preparation, dilevalol (0.1, 0.3, 1.0 and 3.0 micrograms, i.a.) significantly increased femoral blood flow by 12 +/- 6, 27 +/- 6, 84 +/- 31 and 132 +/- 41 ml/min, respectively. In contrast, celiprolol, a beta-blocker with purported vasodilator activity, caused a significant increase in flow of 31 +/- 9 ml/min at a dose of 30 micrograms i.a. Systematic pretreatment with the selective beta 2-antagonist ICI 118,551 virtually abolished dilevalol's vasodilator effect in the dog hindlimb. In conscious spontaneously hypertensive rats, 3 mg/kg i.v. dilevalol reduced blood pressure by 58 +/- 8 mmHg (P less than 0.05) and vascular resistance by 171 +/- 27 dyne.sec.cm-5/100 g (P less than 0.05) but did not change cardiac output significantly. Pretreatment of spontaneously hypertensive rats with ICI 118,551 significantly reduced both dilevalol's antihypertensive and resistance-lowering effects. Oral doses of 10 and 25 mg/kg dilevalol lowered blood pressure by 19 +/- 3 (P less than 0.05) and 37 +/- 5 mmHg (P less than 0.05) in spontaneously hypertensive rats with chronically implanted Doppler flow probes. The lower dilevalol dose reduced mesenteric vascular resistance 38 +/- 6% (P less than 0.05) while the higher dose significantly lowered vascular resistance in the hindlimb, mesenteric and renal vascular beds of spontaneously hypertensive rats by 18 +/- 8, 33 +/- 2 and 43 +/- 4%, respectively. Propranolol lowered neither blood pressure nor regional vascular resistances at the above doses in spontaneously hypertensive rats. Thus, dilevalol promotes a generalized fall in vascular resistance. Furthermore, the present studies illustrate that beta 2-receptor stimulation plays an obligatory role in both the vasodilatory and antihypertensive actions of dilevalol.
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PMID:Role of beta 2-receptor stimulation in the peripheral vascular actions of the antihypertensive dilevalol. 257 92

The efficacy of sustained-release propranolol 160 mg (Inderal LA), bendrofluazide 5 mg and the combination preparation Inderex (bendrofluazide 5 mg and Inderal LA) in the treatment of hypertension was investigated. Twenty-one patients over a wide age range were studied, as it was of particular interest to find whether differing responses across a range of age groups might exist 24 hours post-dosing. Blood pressure control was greater with Inderex than with either Inderal LA or bendrofluazide. No significant difference between different age groups on the three treatments was demonstrated. There was some evidence, not statistically significant, suggesting potassium values to be lower on bendrofluazide and on Inderex. Serum glutamate oxaloacetate transaminase (SGOT) values were raised on bendrofluazide. Inderex is more effective in lowering blood pressure than either bendrofluazide or Inderal LA alone, and as a single capsule given once daily encourages compliance in comparison with combination treatments.
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PMID:Treatment of hypertension with a fixed ratio combination of long-acting propranolol and bendrofluazide, and influence of age of the subject. 259 98

Myocardial contractility of normotensive and spontaneously hypertensive rabbits was determined following an iv bolus injection of propranolol HCl. Left ventricular pressure and dimension were used to calculate the contractility parameters of (dP/dt)max, maximum fiber shortening velocity (Vcf), and the slope of the end systolic pressure-end systolic volume line (ESP-ESV line). Hypertension was induced by a methoxamine HCl iv infusion which mimicked the cardiac effects seen in essential hypertension. Propranolol caused a significant decrease in all contractility parameters (p less than 0.05) within 15 min after administration, with a peak effect occurring after 30-35 mins. The pharmacokinetics and pharmacodynamics of propranolol were fit using Hill's equation in conjunction with the concentration of drug in the theoretical effect compartment. The normotensive group of rabbits had a calculated EC(50) of 12.7 ng/ml, while the hypertensive group had an EC(50) of 6.9 ng/ml, indicating that the hypertensive rabbits were much more sensitive to the propranolol than the normotensive group. In addition, the normotensive group of rabbits demonstrated a much different pharmacokinetic-pharmacodynamic relationship than that of the hypertensive group, indicating that the hypertensive state of the animal has a significant effect upon the concentration-effect relationship.
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PMID:Effect of propranolol on the myocardial contractility of normotensive and spontaneously hypertensive rabbits: relationship of pharmacokinetics and pharmacodynamics. 261 85

The effects of one month's treatment with each of nifedipine, verapamil, diltiazem, propranolol and placebo, given in random order, on fasting plasma glucose, haemoglobin Alc, serum fructosamine, immunoreactive insulin, cholesterol, and triglyceride were studied in a group of 19 patients with hypertension and non-insulin dependent diabetes mellitus. The metabolic effects of the active drugs were generally small but fasting plasma glucose was increased by propranolol from 9.3 +/- 3.0 to 10.4 +/- 3.4 mmol/l (P less than 0.01) (mean +/- SD) and to 10.1 +/- 3.2 mmol/l (P less than 0.05) by nifedipine. Serum fructosamine was increased from 2.75 +/- 0.53 to 2.89 +/- 0.62 mmol/l (P less than 0.05) by diltiazem and to 2.91 +/- 0.65 (P less than 0.05) by propranolol. Verapamil increased fasting serum immunoreactive insulin: diltiazem and propranolol tended to reduce it. Propranolol but not the other drugs significantly increased serum triglyceride. Calcium antagonists may be preferable to beta adrenoceptor blockers for the treatment of hypertensive diabetics. Of the three calcium antagonists we studied, verapamil may have advantages over nifedipine and diltiazem.
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PMID:The effects of verapamil, diltiazem, nifedipine and propranolol on metabolic control in hypertensives with non-insulin dependent diabetes mellitus. 265 57

Quality of life was evaluated in a four-month randomised double-blind trial of verapamil compared with propranolol in the treatment of hypertension in 94 patients in the UK. Scores on a health status index, measuring activity and perceived health, increased in verapamil patients compared to a decrease in propranolol patients (P = 0.01). Measures of psychiatric morbidity also tended to improve with verapamil and deteriorate with propranolol. Propranolol patients reported more symptoms overall compared with verapamil (P less than 0.05). The prevalence of certain symptoms--headaches, weak limbs and slower walking pace, increased significantly with propranolol compared with verapamil, but constipation was more common in verapamil patients (P less than 0.05). After four months, diastolic blood pressure averaged 86.2 mmHg with verapamil and 90.3 mmHg with propranolol (P = 0.02). However, this difference in final blood pressure did not explain the more favourable quality of life scores with verapamil, and the data suggest that health-related well-being is higher with this drug.
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PMID:The effects of verapamil and propranolol on quality of life in hypertension. 266 24

On the basis of echocardiographic investigations changes were analysed of certain haemodynamic parameters in 40 patients aged 21-50 years, mean 44 years, with primary arterial hypertension in stage II according to WHO classification. All patients were randomly chosen to receive for 6-9 weeks propranolol 120-480 mg daily, mean dose 280 mg, or pindolol 10-35 mg daily, mean dose 22 mg daily. The changes developing during the treatment with both drugs in relation to the initial values included the mean arterial blood pressure, the heart rate, the index of cardiac output and the systolic left-ventricular tension. In the studied patients treated with propranolol the heart rate and the ejection volume were decreased more than during pindolol treatment. Propranolol increased evidently the total peripheral vascular resistance and decreased the ejection fraction and the mean velocity of shortening of the circumferential fibres. Pindolol decreased slightly the peripheral vascular resistance and increased the ejection fraction and the mean velocity of shortening of the circumferential fibres. Pindolol, in relation to propranolol, had a more favourable effect on haemodynamics in patients with primary hypertension.
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PMID:[Effect of the treatment with propranolol and pindolol on selected hemodynamic parameters in patients with primary arterial hypertension]. 270 Oct 39


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