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M Küng

Publications and source records attributed to M Küng.

24 records · Page 2Linked to original sources

[Exercise hemodynamics and renin before and after acute beta block in patients with essential hypertension].

Hemodynamic and renin studies at rest and during graded upright ergometry were performed in 21 patients with essential hypertension before and after propranolol. Beta-adrenergic receptor blockade reduced exercise-stimulated cardiac and renin responses significantly more when compared with the corresponding effects at rest. Propranolol increased peripheral resistance at rest but not during exercise. The degree of the individual hemodynamic changes after propranolol correlated better with the corresponding control values than with age or renin. A direct relationship between the percent reduction of heart rate and renin responses after acute beta-blockade indicates a parallel suppression of cardiac and renal receptor functions.

Adrenergic beta-Antagonists↗

Haemodynamic responses to exercise and acute beta-receptor blockade in renin sub-types of essential hypertension.

1. Haemodynamic and renin responses to dynamic exercise before and after intravenous beta-adrenoreceptor blockade with propranolol were compared in twenty-one patients with essential hypertension and either high (n = 7), normal (n = 7) or low plasma renin activity (n = 7). 2. Renin and heart-rate responses to exercise and beta-receptor blockade diminished from high-renin to normal and to low-renin patients, effects which were blunted with increasing age. 3. Among the renin groups cardiac output, stroke volume, diastolic pulmonary artery pressure, systemic pressure and peripheral vascular resistance as well as their changes produced by exercise and acute beta-receptor blockade were not significantly different. 4. Long-term anti-hypertensive propranolol effects correlated with pre-treatment renin status, renin stimulation and its suppression by acute beta-receptor blockade as well as with the exercise tachycardia and the patient's age. 5. The results suggest different adrenergic control mechanisms in renin sub-types of essential hypertension, age being a modulating factor.

Adult↗

Once daily dosage beta-blockade: antihypertensive efficacy of slow release oxprenolol as related to renin and age.

A single daily dose antihypertensive therapy with a new slow-release (SR) form of the beta-adrenoceptor blocking agent oxprenolol was as effective as a standard tid beta-blocker regimen in maintaining therapeutic effects over 24 hours. The good overall response rate (target larger than or equal to mmHg diastolic) of 67% was achieved in eight of the 11 high renin patients and 16 out of the 20 normal renin ones; the five low renin patients, who were also older, proved to be non-responsive. In terms of age, 83% of the patients aged under 40 years showed a reduction in diastolic pressure to larger than or equal to 95 mmHg, this percentage being significantly better than the 50% response rate in the 40--56-year-olds. In nine of the 12 beta-blocker non-responders the diastolic blood pressure was reduced to larger than 95 mmHg by adding a diuretic, and in four of the nine, all of them low renin patients, this effect persisted in response to diuretics alone. Oxprenolol SR suppresses renin acutely (59%) and chronically (62%), and it blunts the renin stimulatory effects of diuretics.

Adolescent↗

Antihypertensive beta blocking action as related to renin and age: a pharmacologic tool to identify pathogenetic mechanisms in essential hypertension.

Three hundred fifteen patients with essential hypertension were classified according to low (18 percent), normal (59 percent) or high (23 percent) renin-sodium index. The proportion of patients with low renin hypertension progressively increased with increasing age and blood pressure, there being no difference between the sexes. Two high renin groups emerged: a younger group with early moderate hypertension, and an older group with severe hypertension consequent to possibly ischemic renal disease. Long-term beta blocking monotherapy in 137 patients resulted in a reduction of idastolic pressure to 95 mm Hg or less in 65 percent: 85 percent in those with high and 73 percent in those with normal renin activity; pressure was reduced to this level in only 1 of 24 patients (4 percent) with a low renin index. Antihypertensive efficacy was also related to age, since diastolic pressure was normalized in 80 percent of patients under age 40 years, in 50 percent of those aged 40 to 60 years, but in only 20 percent of those over age 60 years. Age may heolp in patient selection but is no substitute for the more reliable renin index, especially in patients over age 40 years, or with high pressure. Using studiew with propranolol as a standard, similar renin responses were obtained with two cardioselective beta1 type blocking drugs, atenolol and metoprolol, as well as with two nonselective beta2+1 receptor antagonists, LL21945 exhibiting prolonged receptor affinity and oxprenolol in slow release form. These long-acting drugs, which proved effective in single daily doses, could be of value in improving patient compliance...

Adrenergic beta-Antagonists↗