Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0085580 (essential hypertension)
 14,686 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Mean arterial blood pressure, forearm vascular resistance, plasma norepinephrine, plasma renin activity and aldosterone responses to graded lower body negative pressure and tilt at 80 degrees were examined in 10 men with mild to moderate essential hypertension before and after 12 weeks of diltiazem (240 to 360 mg/day) therapy. Diltiazem therapy lowered basal supine systolic and diastolic blood pressures without affecting basal heart rate. Mean arterial blood pressure and forearm vascular resistance were decreased from 114 +/- 1.5 to 105 +/- 1 mm Hg, p less than 0.01 and from 29.3 +/- 3.5 to 18.9 +/- 2.1 units, p less than 0.01, respectively. Diltiazem therapy had no effect on basal supine levels of norepinephrine, plasma renin activity or aldosterone, nor on the responses of these hormones to lower body negative pressure. Diltiazem did decrease the forearm vascular resistance responses to lower body negative pressure and tilt. Diltiazem abolished an orthostatic increase (10 +/- 0.3 mm Hg) in mean arterial blood pressure and this was associated with a greater plasma norepinephrine response to tilt. These results suggest that diltiazem decreases vascular resistance through a reduction in the postjunctional effects of norepinephrine on vascular smooth muscle.
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PMID:Effects of diltiazem on hormonal and hemodynamic responses to lower body negative pressure and tilt in patients with mild to moderate systemic hypertension. 390 20

Treatment of hypertension with diuretics, beta blockers and alpha blockers may be associated with adverse effects on exercise performance, serum lipids and blood chemistries, as well as with orthostatic effects and fluid retention. A randomized, double-blind, placebo-controlled trial of a sustained-release preparation of diltiazem as sole therapy for moderate essential hypertension was conducted. Diltiazem was administered 2 times a day (360 mg/day) to 16 patients and placebo to 14 patients in a 12-week study. Average supine blood pressure with diltiazem therapy fell from 161/100 to 144/87 mm Hg without fluid retention or orthostatic effects. In an open-label study, patients from the placebo and diltiazem groups continued with diltiazem therapy. At an average of over 8 months, supine blood pressure on diltiazem was 147/88 mm Hg, and after withdrawal to single-blind placebo, average supine blood pressure increased to 173/104 mm Hg. All changes were significant compared with baseline and placebo (p less than 0.01). On diltiazem therapy, maximal treadmill exercise was increased by an average of 55 seconds (p less than 0.01), whereas heart rate, blood pressure and double product (heart rate X blood pressure) were reduced at submaximal exercise, and heart rate and double product were reduced at maximal exercise. No changes in serum glucose, potassium or uric acid were found. No adverse effects on serum lipids occurred. Diltiazem treatment was associated with an increase in high-density lipoprotein cholesterol (52 to 60 mg/dl, p less than 0.006) and a decrease in total cholesterol:high-density lipoprotein cholesterol ratio (4.7 to 4.2, p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Effects of diltiazem on serum lipids, exercise performance and blood pressure: randomized, double-blind, placebo-controlled evaluation for systemic hypertension. 390 22

Although the calcium channel blocker diltiazem has been shown to be an effective antihypertensive agent, its effect on renal function, salt and water excretion, and body fluid composition has not been well characterized in patients with primary hypertension. Therefore, these parameters were prospectively studied in 18 subjects with primary hypertension after placebo and 8 weeks of diltiazem monotherapy. Diltiazem monotherapy was confirmed to be an effective antihypertensive agent. Although mean arterial pressure was reduced from 121 to 108 mm Hg, diltiazem had no overall effect on glomerular filtration rate, renal plasma blood flow, salt and water excretion, or body fluid composition. Renal vascular resistance, however, was decreased. In subjects with pretreatment glomerular filtration rates of 80 ml/min/1.73 m2 or less, diltiazem therapy was associated with marked improvement in glomerular filtration rate (48%) and effective renal plasma flow (36%). Since the filtration fraction was unchanged, changes in glomerular filtration rate may have been related to the attenuated intrarenal effects of angiotensin II or norepinephrine, or both.
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PMID:Renal effects of diltiazem in primary hypertension. 394 75

We studied blood pressure, arterial diameter, and blood flow of the brachial artery in patients with sustained essential hypertension before and after administration of the vasodilating drugs nitroglycerin, captopril, dihydralazine, diltiazem, and isosorbide dinitrate (ISDN). The diameter and the blood flow of the brachial artery were measured with a pulsed Doppler device which allowed the angle between the ultrasound beam and the vessel axis to be determined with a precision better than 2%. Nitroglycerin and captopril decreased blood pressure slightly but increased arterial diameter markedly. Dihydralazine, diltiazem, and ISDN decreased blood pressure similarly and significantly and also reduced forearm vascular resistance. Dihydralazine reduced arterial diameter (p less than 0.001), but did not change brachial blood flow. Diltiazem and ISDN increased the arterial diameter markedly (p less than 0.001 and p less than 0.01, respectively), but only the former increased brachial blood flow. We conclude that antihypertensive drugs that dilate small arteries can either reduce (dihydralazine) or increase (nitroglycerin, captopril, diltiazem, ISDN) the caliber of large peripheral arteries and thus have different effects on peripheral blood flow.
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PMID:Action of vasodilating drugs on small and large arteries of hypertensive patients. 619 61

The pharmacokinetics, clinical efficacy, and adverse effects of three calcium-channel blocking agents--verapamil, nifedipine, and diltiazem--are reviewed. Verapamil, nifedipine, and diltiazem are absorbed well after oral dosing, but absolute bioavailability of each is reduced substantially by a first-pass effect. Each drug is metabolized extensively (verapamil and diltiazem to moderately active metabolites) by the liver. A substantial percentage of each drug is bound to plasma proteins, but the binding is of clinical importance only for nifedipine (92--98% protein bound). Intravenous verapamil has become the agent of first choice for treatment of acute paroxysmal supraventricular tachycardia (PSVT); use of chronic oral verapamil therapy for prophylaxis remains controversial. Verapamil and diltiazem have been evaluated with mixed results for atrial flutter and fibrillation. For treatment of myocardial ischemia, calcium-channel blockers may be of some value (possibly in combination with nitrates of B blockers). All three agents have been studied in patients with exertional angina with good results. Calcium-channel blockers appear to be equal with nitrates for treatment of variant angina. Patients with hypertropic cardiomyopathy have been treated with verapamil and nifedipine with promising results. Nifedipine has been effective for treatment of essential hypertension. Adverse effects of calcium-channel blockers have been relatively minor or infrequent. Diltiazem overall has the best side-effect profile, with adverse effects causing discontinuation of therapy in about 2--10% of patients; verapamil in intermediate (8--10%) and nifedipine the worst (17%) in this respect. The most common side effects generally are fatigue, headache, dizziness, skin rash, and peripheral edema. While they generally should be reserved for patients in whom more conventional therapy has failed (except those with PSVT), calcium-channel blockers appear to have a valid role as reserve agents for exertional and variant angina, cardiomyopathy, and hypertension.
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PMID:Update on calcium-channel blocking agents. 635 66

The hypotensive effect of acute and longterm, intravenous and oral administration of the calcium antagonist, diltiazem, was investigated in 8 normotensive volunteers and 55 patients with essential hypertension. Diltiazem i.v. infusion of 45 mg/h (0.5 mg/min, then 1.0 mg/min, each for 30 min rapidly decreased both blood pressure (BP) from 164 +/- 22/98 +/- 8 to 144 +/- 15/86 +/- 9 mmHg (mean +/- SD) and total peripheral resistance from 32.6 +/- 8.4 to 25.3 +/- 5.4 mmHg/l/min (p less than 0.001), and increased stroke volume from 58.2 +/- 9.5 to 64.2 +/- 8.6 ml/beat (p less than 0.05). It altered neither heart rate nor cardiac output in the hypertensives (n = 10). Oral diltiazem 60 mg rapidly decreased BP from 155 +/- 10/103 +/- 6 to 142 +/- 12/90 +/- 8 mmHg after 3 hours (p less than 0.01/p less than 0.001) in hypertensives (n = 8), but not in normotensives (n = 8). Diltiazem 90 mg p.o. decreased BP from 157 +/- 15/102 +/- 9 to 129 +/- 13/83 +/- 8 mmHg (p less than 0.01) in hypertensives (n = 15), and reduced the heart rate from 71 +/- 8 to 65 +/- 8 beats/min (p less than 0.01). The drug did not change plasma renin activity either in normotensives or hypertensives. The fall in diastolic BP was correlated with the plasma diltiazem concentration (r = 0.910, n = 6, p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Hypotensive effects of diltiazem to normals and essential hypertensives. 636 Jun 93

In a double-blind, parallel, 12-week trial, antihypertensive effects of diltiazem and reserpine were compared in 107 patients with essential hypertension. Diltiazem reduced blood pressure from 176/100 mmHg to 154/86 mmHg after 12 weeks, and reserpine reduced blood pressure from 171/96 mmHg to 155/85 mmHg. The difference between diltiazem and reserpine was not statistically significant. However, among a subset of patients given 180 mg/day of diltiazem, a significantly better antihypertensive effect was achieved than among a subset given 0.3 mg of reserpine. The incidence of side effects and complications in the diltiazem group was about one half that in the reserpine group (12.3% and 27.1%, respectively). Side effects of diltiazem were mild, and the drug was extremely well tolerated. These results show that diltiazem is an effective antihypertensive drug for the treatment of mild to moderate essential hypertension.
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PMID:Diltiazem for treatment of essential hypertension: a double-blind controlled study with reserpine. 639 69

Blood pressure, heart rate, and arterial diameter of the brachial artery were studied in patients with sustained essential hypertension before and after administration of three vasodilating drugs: dihydralazine, diltiazem, and dinitrate isosorbide (ISDN). The diameter of the brachial artery was measured using a pulsed Doppler device, enabling the angle between the ultrasound beam and the vessel axis to be evaluated with a precision inferior to 2 percent. The three drugs had similar effects in decreasing the blood pressure and the forearm vascular resistance. Dihydralazine reduced the arterial diameter (p less than 0.001) and increased heart rate. Diltiazem and ISDN increased markedly the arterial diameter (p less than 0.001) but did not change heart rate. Dihydralazine decreased the tangential tension of the arterial wall, while diltiazem and ISDN did not. The study provided evidence that, with vasodilating drugs, the changes in the caliber of peripheral large arteries, which are a determinant of wall arterial tension, can influence the baroreflex-mediated tachycardia caused by use of the drugs.
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PMID:Baroreflex response and vasodilating drugs in essential hypertension. 682 28

The calcium antagonists, diltiazem and nifedipine, are effective in mild-to-moderate chronic essential hypertension. The overall responder rate is 80%. Diastolic blood pressure is lowered by 10-15% at rest and during exercise. Systolic blood pressure is reduced only at rest. Heart rate may be unchanged by nifedipine and lowered by diltiazem. Both drugs lead to a decrease of peripheral resistance by 15-20% at rest and 30% during work. As a consequence of afterload reduction, cardiac output, stroke index, and stroke work index increased by 17, 21, and 7% with nifedipine and 34, 26, and 20% with diltiazem. During exercise, these changes are even more pronounced. However, pulmonary artery pressure and pulmonary vascular resistance are reduced only by nifedipine, not by diltiazem. Presumably due to this combined preload and afterload reduction, nifedipine therapy is associated with a reflex activation of the sympathetic nervous system in all cases, with an increase in norepinephrine plasma concentration and, sometimes, tachycardia. Diltiazem, however, has the advantage of being a potent blood pressure-lowering agent, with afterload reduction and increased stroke index, with less pronounced catecholamine increase, and without tachycardia. Side effects with this drug are rare, and long-term therapy is well tolerated.
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PMID:Role of calcium antagonists in the treatment of essential hypertension. 683 51

Diltiazem HCl was administered p.o. at a fixed daily dose level of 180 mg to patients with essential hypertension, and the hypotensive effect of the drug was investigated. The following results were obtained: diltiazem HCl given alone exhibited a hypotensive effect on systolic pressure in 88.9% of the patients and on diastolic pressure in 66.7% of the patients. The concurrent use of diltiazem HCl with trichlormethiazide exerted a hypotensive effect on patients who were nonresponsive to diltiazem HCl alone. As regards side effects, one patient complained of gastric fullness and one of dizziness. However, the symptoms were so mild that further continuation of diltiazem HCl therapy was possible. From the results obtained, it is concluded that diltiazem HCl can effectively be used clinically as a hypotensive drug.
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PMID:Clinical study on the hypotensive effect of diltiazem hydrochloride. 721 50


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