PubMed Health⌕ Search

Biomedical subjects

L Woie

Publications and source records attributed to L Woie.

18 recordsLinked to original sources
PubMed1991

Low-frequency transcutaneous nerve stimulation in mild/moderate hypertension.

Low-frequency peripheral nerve stimulation may induce widespread cutaneous and muscular vasodilatation in animals and humans due to sympatho-inhibition. This response has in humans been shown to be associated with a lowering of the systemic vascular resistance and arterial pressure. In the present study the effectiveness of low-frequency (2 Hz) transcutaneous electrical nerve stimulation (TNS) has been examined in 46 patients, all 41-43 years of age, with a primary diagnosis of uncomplicated mild/moderate hypertension (90-115 mmHg diastolic pressure). The study was designed blind with matched controls in a TNS group and a placebo group. The blood pressure was measured objectively with an automatic monitor. In a short-term experiment TNS produced a significant lowering of systolic, mean arterial, and diastolic pressures amounting to 8 mmHg (P less than 0.01), 6 mmHg (P less than 0.01), and 4 mmHg (P less than 0.02), respectively. In a long-term study, after 2 weeks of daily stimulation, a similar depression was recorded with no stimulation on the day of examination. An eventual clinical use of the depressor effect of TNS demands further clinical research.

Adult↗
PubMed1990

Effects of an angiotensin converting enzyme (ACE) inhibitor on plasma endorphin level.

1. In addition to their antihypertensive effect, ACE inhibitors have been reported to increase general well-being, general health and vitality and work performance. The cause of these effects is not known. A possible mechanism may be release of beta-endorphins. 2. In the present study changes in plasma concentration of beta-endorphins on days with ACE inhibitor treatment (n = 12) and on non-treatment control days (n = 12) were compared in 6 patients. 3. Both on control and treatment days the beta-endorphin level fell, by 7.1 and 10.0%, respectively, from 8.00 a.m. to 8.00 p.m., reflecting the known diurnal rhythm of this opioid. This difference between the control and treatment days is not statistically significant. 4. The study should be extended to determine endorphin concentration in the cerebrospinal fluid, and other opioids should be looked for.

Angiotensin-Converting Enzyme Inhibitors↗
PubMed1990

Transcutaneous nerve stimulation in patients with coronary arterial disease: haemodynamic and biochemical effects.

Low-frequency transcutaneous nerve stimulation (TNS) is known to produce widespread and prolonged vasodilation in skin and muscles. In the present study the effects of low-frequency TNS on coronary and systemic haemodynamics, myocardial blood flow, myocardial oxygen consumption, myocardial free fatty acid and lactate uptake were measured at rest in 16 normotensive patients, with coronary heart disease, undergoing diagnostic cardiac catheterization. In addition, vasoactive intestinal polypeptides (VIP) and noradrenaline were measured in the coronary sinus and the aorta. The study was randomized and double-blind, with half of the patients serving as placebo controls. A stimulation period of 20 min caused a significant lowering of mean femoral arterial pressure and systemic vascular resistance measured at 15 and 30 min after the start of TNS (P less than 0.01). There was no significant change in the other parameters mentioned. The hypotonic effect is considered to be due to increased peripheral microcirculation resulting from sympatho-inhibition.

Coronary Circulation↗
PubMed1989

Effect of metoprolol on early exercise-induced ST-segment changes and ventricular arrhythmias in patients with suspected acute myocardial infarction.

One-hundred and ninety-seven consecutive patients admitted for suspected acute myocardial infarction were randomized to double-blind treatment with intravenous followed by oral metoprolol or matching placebo within 24 hours (mean 6.9 hours) after onset of symptoms. A symptom-limited exercise test was performed 15 days after admission in 132 patients (70 patients receiving metoprolol; 62 placebo). Patients treated with metoprolol had a lower observed frequency of exercise-induced ST-segment elevation (11.4% vs. 22.6%; P less than 0.05) and less ventricular arrhythmias (7.1% vs. 19.4%; P less than 0.05) on the predischarge exercise test compared to placebo-treated patients; however, ST-segment depressions were equally distributed to the two treatment groups. Mean exercise capacity was the same in the two groups. Early administration of metoprolol to patients with suspected acute myocardial infarction reduces early exercise-induced parameters related to a bad prognosis and may therefore improve the long-term prognosis without reducing physical performance.

Arrhythmias, Cardiac↗
PubMed1987

Increase in vasoactive intestinal polypeptides (VIP) by the angiotensin converting enzyme (ACE) inhibitor lisinopril in congestive heart failure. Relation to haemodynamic and hormonal changes.

1. The effects of the angiotensin-converting enzyme (ACE) inhibitor lisinopril on plasma vasoactive intestinal polypeptides (VIP) and plasma noradrenaline, adrenaline and dopamine were studied in 12 patients with congestive heart failure over two consecutive 48-hr periods. The first day in each period served as a treatment day and the second as a control day. 2. A parallel monitoring was made of various hormonal parameters related to the renin-angiotensin-aldosterone system, and a right-heart catheter was used to monitor haemodynamics at rest. 3. Potent inhibition of the renin-system (as demonstrated by decreases in angiotensin converting enzyme (ACE) activity, angiotensin II and plasma aldosterone) together with improved haemodynamics (decreases in mean right atrial pressure, mean pulmonary arterial pressure, mean pulmonary capillary wedge pressure and mean systemic arterial pressure) were recorded. 4. Plasma VIP was significantly increased by a mean of 20.3% (P less than 0.01) on the lisinopril treatment days compared with the control days, whereas circulating catecholamines showed no significant pattern of change. 5. It is postulated that the potent vasodilatory neuromodulator VIP is implicated in the ACE inhibitor effects. 6. The ACE is a non-specific peptidase that previously has been implicated in the potentiation of other vasoactive endogenous systems (kinins and enkephalins).

Adult↗
PubMed1986

Acute hemodynamic and hormonal effects of lisinopril (MK-521) in congestive heart failure.

The acute hemodynamic and hormonal effects of the oral angiotensin-converting enzyme (ACE) inhibitor lisinopril (MK-521) were assessed over a period of 96 hours in 12 patients with heart failure. This compound is the lysine analogue of enalaprilat (MK-422), is biologically active following absorption, and is cleared via the urine without any known metabolic transformation. Single doses of lisinopril, ranging from 1.25 mg to 10 mg, were administered on days 1 and 3, each followed by 48 hours of intensive hemodynamic observation. Across all doses, maximal reductions in mean arterial pressure (17.2%), mean pulmonary capillary wedge pressure (28%), and systemic vascular resistance (25.6%) were observed compared to baseline values. No significant changes in heart rate were recorded. Arterial blood was sampled at frequent intervals for angiotensin II, ACE activity, plasma renin activity, renin substrate, plasma aldosterone, and serum drug levels. Right atrial blood was sampled simultaneously for angiotensin I, thus permitting assessment of the degree of pulmonary conversion to angiotensin II. The results indicate potent inhibition of the renin-angiotensin-aldosterone system along with hemodynamic efficacy over a period exceeding 24 hours. Frequent clinical follow-up on long-term chronic therapy has revealed no adverse experience.

Adult↗
PubMed1986

Increase in plasma vasoactive intestinal polypeptide (VIP) in muscular exercise in humans.

We have previously shown that plasma vasoactive intestinal polypeptide (VIP) is increased in normal subjects by low-frequency transcutaneous nerve stimulation. The latter may also increase short-term physical performance in athletes (running, swimming and ergometer cycling). The present study examines whether the plasma VIP level is similarly increased in short-term ergometer exercise in seven healthy volunteers. A group of four patients with angina pectoris were included, since a lowered concentration of VIP is found in diseased heart tissue. In the group of healthy subjects, ergometer exercises with progressive increases in workload until exhaustion, lasting from 16 to 32 min (mean 26 min) and with a corresponding maximum energy output of 1500 to 5100 W (mean 3560 W), resulted in an increase in plasma VIP concentration from a pre-stimulatory level of 3.3 pmol . l-1 to 5.3, 5.2 and 5.6 pmol . l-1, measured 3, 10 and 20 min respectively, following termination of the exercise, i.e. a maximal 70% increase. In the patients with angina pectoris there was no significant VIP increase (cycling time 7-15 min, work performed 400-1350 W). Possible triggering mechanisms for VIP release and its source are discussed.

Adult↗
PubMed1984

Acute hemodynamic and hormonal effects of MK-521 in congestive heart failure.

The acute hemodynamic and hormonal effects of the oral angiotensin converting enzyme (ACE) inhibitor MK-521 were assessed over a period of 96 hours in 6 patients with heart failure. This compound is the lysine analogue of enalapril diacid (MK-422) and is biologically active following absorption. Dosages ranging from 1.25 mg to 5.0 mg were administered on days 1 and 3, followed by 48 hours intensive hemodynamic observation. Marked reduction in mean arterial pressure (25.2%), pulmonary capillary wedge pressure (47.3%), and systemic vascular resistance (34.5%) was observed. Arterial blood was sampled at frequent intervals for angiotensin I (AI), angiotensin II (AII), plasma renin activity, renin substrate, plasma aldosterone, urinary aldosterone, ACE activity, and serum drug levels. Right atrial blood was sampled simultaneously for AI and AII thus permitting reliable assessment of the degree of pulmonary conversion to angiotensin II. Prolonged inhibition of the renin-angiotensin-aldosterone system was confirmed and corresponded to drug concentration. The results indicate hemodynamic efficacy and potent ACE inhibition over a period exceeding 24 hours.

Adult↗