Search PubMed⌕ Search

Biomedical subjects

R Eggertsen

Publications and source records attributed to R Eggertsen.

44 records · Page 3Linked to original sources
PubMed1984

Beta-adrenoceptor blockade and vasodilatation in essential hypertension. Hemodynamic studies at rest and during exposure to stress.

The purpose of this study was to evaluate the acute and long-term effects on blood pressure and hemodynamics both at rest and during acute exposure to loud noise of drugs with beta-adrenoceptor blocking and vasodilating properties. Prizidilol and carvedilol both act as nonselective beta-blocking and precapillary vasodilating compounds. Prizidilol (200 mg X 2) was compared to propranolol (80 mg X 2) plus hydralazine (25 mg X 2) and showed similar antihypertensive effect in a long-term double-blind randomized trial. Carvedilol was evaluated acutely with invasive (dye-dilution) and noninvasive (plethysmography) technique and showed an acute antihypertensive effect without causing a rise in TPR and with a decrease in regional resistance in the fore-arm. Acutely, carvedilol (25 mg and 50 mg) decreased blood pressure and regional resistance (50 mg) in contrast to propranolol (80 mg) which did not lower blood pressure acutely and caused an increase in regional resistance. In a long-term double-blind, randomized comparison, both propranolol (80 mg X 2) and carvedilol (25 mg X 2 and 50 mg X 2) showed a useful antihypertensive effect. After 29 days, however, it was still possible to demonstrate an acute decrease in resistance with carvedilol (50 mg) after tablet intake, indicating the vasodilating activity of this compound. When patients with essential hypertension were exposed to an even broad band noise (100 dBA), there was a rise in blood pressure due to an increase in TPR. Alpha 1-adrenoceptor blockade (prazosin 2 mg) prevented the rise in TPR but blood pressure increased in spite of this due to a rise in CO. Moreover, nonselective beta-adrenoceptor blockade and alpha 1-adrenoceptor blockade in combination (labetalol 200 mg) were unable to prevent the rise in blood pressure induced by noise. Finally, precapillary vasodilatation and beta-adrenoceptor blockade (prizidilol 400 mg) given as long-term treatment were also inefficient in preventing the noise-induced (105 dBA) rise in blood pressure. The absolute level of blood pressure obtained, however, was significantly lower than during placebo administration.

Adrenergic beta-Antagonists↗
PubMed1983

Circulatory effects of noise.

Thirteen patients with mild essential hypertension, mean age 44 years (range 21-59), were studied during "stress" before and after postsynaptic alpha-adrenoceptor blockade and combined postsynaptic alpha- and non-selective beta-adrenoceptor blockade. Loud broad band noise (100 dBA for 10 min) was used as the stress stimulus. Exposure to noise caused a significant increase in systolic (7%, p less than 0.05), diastolic (9%, p less than 0.01) and mean arterial pressure (6%, p less than 0.01). The blood pressure elevation was caused by an increase in total peripheral resistance (12%, p less than 0.05). There was no significant change in heart rate, stroke volume or cardiac output. The blood pressure response during noise stimulation was not affected by postsynaptic alpha-adrenoceptor blockade (prazosin, 2 mg orally). The hemodynamic reaction pattern, however, was totally reversed. Thus, the cardiac output increased significantly (9%, p less than 0.05), while the total peripheral resistance tended to decrease. Combined postsynaptic alpha- and non-selective beta-adrenoceptor blockade (labetalol, 200 mg orally) inhibited the increase in systolic blood pressure caused by noise, while the diastolic and mean arterial pressures still increased significantly (5%, p less than 0.01). Labetalol effectively blocked the stress-induced increase in total peripheral resistance and there was no significant increase in cardiac output after combined alpha- and beta-adrenoceptor blockade. Exposure to noise caused a significant increase in circulating noradrenaline (20%, p less than 0.05). Plasma adrenaline and plasma renin activity were not affected by noise stimulation. These results suggest that blood pressure elevation is essential during "stress" but that the hemodynamic pattern causing blood pressure elevation may vary and may be affected by pharmacological blockade of various parts of the sympathetic nervous system.

Adult↗
PubMed1983

Ketanserin in hypertension. Early clinical evaluation and dose finding study of a new 5-HT2 receptor antagonist.

Ketanserin, a new 5-hydroxy-tryptamine antagonist, was given at three different dosage levels (double-blind, randomized) in a dose finding study for 2 months to 31 patients with mild to moderately severe essential hypertension. Treatment with ketanserin was then continued until 9 months had been completed. A significant antihypertensive effect was demonstrated at daily dosages of 20 mg t.i.d. or 40 mg t.i.d. The antihypertensive effect was similar to that of previous multiple drug treatment with conventional drugs. However, 60 mg t.i.d. was not acceptable, at least not as initial dosage. At this dose level, 8 out of 10 patients had to be withdrawn from the study during the initial phase due to unwanted effects. It is conceivable that alpha 1-adrenoceptor blockade may have played a role at this dose level, since postural reactions were observed which was otherwise not the case during this study. Ketanserin is a new and interesting alternative in the treatment of hypertension. At the same time it offers a tool by which the role of 5-hydroxy-tryptamine in the regulation of arterial pressure can be investigated.

Adult↗
PubMed1982

Effects of treatment with nifedipine and metoprolol in essential hypertension.

In a double-blind trial 26 patients with essential hypertension were treated with nifedipine or placebo for 8 weeks, following a 4-week run-in-placebo period in all patients. The daily dosage of nifedipine during this phase was 10 mg 3 times daily. Metoprolol was then added to the therapeutic regimen of both groups for a further 12 weeks. Both nifedipine and metoprolol used as mono-therapy caused statistically significant reductions of arterial pressure. The addition of metoprolol to nifedipine tended to reduce blood pressure further, but blood pressures were not significantly lower than during nifedipine mono-therapy. Side-effects were few and only two patients had to be withdrawn during active therapy, one for headaches during nifedipine therapy, and another for asthma during metoprolol treatment. Combined therapy with a beta-adrenoceptor blocking agent, such as metoprolol, and a calcium antagonist with vasodilation properties, such as nifedipine, offers a theoretically interesting approach in the treatment of hypertension, even though the practical outcome in the present study probably suffered from an inadequate dose of nifedipine during the period of combined therapy.

Adult↗