Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0020538 (hypertension)
 170,190 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Data on the influence of antihypertensive drug treatment on mortality of hypertensive rats are reviewed. Dihydropyridine calcium antagonists, verapamil, the angiotensin-converting enzyme (ACE) inhibitor captopril, and a triple combination of reserpine, hydralazine, and chlorothiazide normalized or markedly prolonged survival. Captopril was less effective in sodium chloride-induced, low-renin Dahl rat hypertension. Dihydralazine prolonged but did not nearly normalize survival. The K(+)-channel activator minoxidil was relatively ineffective. Data on diuretics or beta-blockers are insufficient or unavailable. Calcium antagonists nitrendipine and nimodipine and the ACE inhibitor captopril improved survival and prevented vascular lesions and calcinosis even at doses that failed to achieve normotension. All drugs that normalized survival also reduced heart weights. Minoxidil invariably increased heart weights and failed to improve survival. (Di)hydralazine assumed an intermediate position.
 ...
PMID:Effects of different antihypertensive drug classes on survival in animal models. 171 94

Six control dogs, six dogs treated with 1.5 mg/kg b.i.d. quinapril, and six dogs treated with 8 mg/kg q.d. minoxidil underwent 6 hours daily of hindquarter compression for 9 weeks. Minoxidil significantly decreased baseline blood pressure (-17 mm Hg; p less than or equal to 0.01), whereas quinapril decreased baseline blood pressure 11 mm Hg but not significantly (p = 0.15). Hindquarter compression elicited blood pressure increases in all three groups (control +18, quinapril +13, minoxidil +19 mm Hg). After 9 weeks, left ventricular mass in control dogs increased 22% (p less than 0.004); a similar increase was seen in minoxidil-treated dogs (+22%, p less than 0.0001) but not in the quinapril-treated group (+4%, p less than 0.15). The increase in left ventricular mass in control dogs was concentric (increased epicardial volume only), whereas in the minoxidil group, the hypertrophy was eccentric (both epicardial and endocardial volumes increased). The minimal hypertrophy in the quinapril group was concentric (no change in epicardial, but a decrease in endocardial volume). Quinapril had little hypotensive effect, but prevented the development of left ventricular hypertrophy, whereas minoxidil did not prevent hypertrophy in spite of its hypotensive effect. The mechanism of this differential effect of direct vasodilation versus converting enzyme inhibition on left ventricular hypertrophy is not fully elucidated. The results with quinapril suggest that some antihypertensive agents may positively affect left ventricular hypertrophy in spite of the absence of a large effect on baseline blood pressure or on blood pressure reactivity.
Hypertension 1991 Jun
PMID:Quinapril, an angiotensin converting enzyme inhibitor, prevents cardiac hypertrophy during episodic hypertension. 182 58

Minoxidil - a therapeutic agent used in the control of hypertension and which has been implicated in modulation of hair follicle activity - has been shown to influence certain aspects of the physiology of cultured endothelial cells. It suspends cell proliferation in a reversible manner, appears to influence cell morphology in a dose dependent way, does not significantly alter (qualitatively) protein synthesis and does not inhibit cell migration. These results demonstrate similarities between endothelial cells and keratinocytes and dermal fibroblasts and differences between endothelial cells and dermal papilla cells, follicular root sheath fibroblasts and neutrophils in their response to this agent.
 ...
PMID:The effect of minoxidil on endothelial cells in vitro. 276 62

Minoxidil is a potent antihypertensive which is reserved for severe cases. A 58-year-old man admitted for evaluation of progressive dyspnea and peripheral edema had been taking Minoxidil, Normiten and Lasix for severe hypertension. Echocardiography disclosed a massive pericardial effusion but there were no signs of tamponade. Discontinuation of Minoxidil resulted in complete clearance of the pericardial fluid within 3 months. Awareness of this potentially fatal side-effect of Minoxidil is mandatory.
 ...
PMID:[Massive pericardial effusion following minoxidil]. 279 35

In rats with severe two-kidney, one clip (2-K,1C) hypertension the time-course of changes in left and right ventricular (LV and RV) weight and LV dimensions was assessed following initiation of chronic treatment with minoxidil, enalapril or removal of the clipped kidney in relation to changes in blood pressure (BP) and sympathetic activity, as well as plasma and blood volumes. Minoxidil decreased BP markedly, but tolerance to the antihypertensive effect developed after 2-3 weeks. In contrast, enalapril or uninephrectomy caused a rapid and persistent normalization of BP. Significant increases in LV and RV weight occurred after 3-5 weeks of treatment with minoxidil. Left ventricular wall thickness decreased over the initial 1-2 weeks and then returned to untreated levels. Left ventricular internal dimensions showed an increase after 1-2 weeks of minoxidil, which persisted with more prolonged treatment. With enalapril, regression to normal occurred for both LV and RV weight within 1 week of treatment. Following uninephrectomy a more gradual regression took place and normal cardiac weight was not obtained until 3 weeks. Indices of sympathetic activity (plasma catecholamines, BP response to hexamethonium or heart rate) did not differ significantly in minoxidil treatment versus untreated hypertensive rats from 2 to 35 days of treatment. A significant increase in heart rate was found after 1 day of minoxidil and a decrease after enalapril. Plasma and blood volumes were elevated in minoxidil-treated rats from 7 to 35 days, as well as initially after uninephrectomy. Therefore, in 2-K, 1C hypertensive rats long-term treatment with minoxidil induces both RV hypertrophy and LV eccentric hypertrophy. Changes in cardiac volume load may play a major role in the differing effects of different antihypertensive therapies on cardiac hypertrophy.
 ...
PMID:Time-course of changes in cardiac hypertrophy and pressor mechanisms in two-kidney, one clip hypertensive rats during treatment with minoxidil, enalapril or after uninephrectomy. 288 53

Minoxidil (Loniten), a potent predominant arteriolar vasodilator, provides prompt and effective reduction of blood pressure in many patients with severe hypertension. Minoxidil results, however, in profound reflex tachycardia and increased plasma volume almost always necessitating concomitant use of beta-adrenergic blocking agents and diuretics. Hypertrichosis and massive fluid retention are troublesome adverse reactions that may require discontinuation of minoxidil and initiation of an alternative antihypertensive agent. When minoxidil is discontinued, diuretic dosage requires re-evaluation and possible tapering to prevent volume depletion. Volume depletion is a risk factor in patients with persistent peripheral edema, sodium deprivation or dehydration; these states may interfere with physiologic mechanisms that maintain adequate cerebral perfusion upon standing, triggering orthostatic hypotension and potential syncope. Hypertension clinic visits should routinely include supine followed by sitting and standing blood pressure determinations to ensure detection of orthostatic hypotension. Described in the article is a case study in which a patient developed severe orthostatic hypotension one month after minoxidil was discontinued. Pathophysiologic mechanisms are discussed.
 ...
PMID:Orthostatic hypotension occurring after discontinuation of long-term minoxidil therapy. 317 16

Minoxidil is a potent peripheral vasodilator used to treat patients with severe hypertension that is unresponsive to other medications. Hypertrichosis of the forehead, face, neck, shoulders, upper part of the arms, and legs is a frequent side effect that occurs in the majority of patients that use this drug. This phenomenon appears to be due to increased blood flow to hair follicles, with resultant excessive hair growth. We describe a patient with severe hypertrichosis of the external ear canal resulting in chronic otitis externa and hearing loss.
 ...
PMID:Severe hypertrichosis of the external ear canal during minoxidil therapy. 339 Mar 39

The antihypertensive efficacy of minoxidil and captopril was compared in 23 males with essential or renal parenchymatous hypertension refractory to conventional antihypertensive drug therapy. Following a pretreatment period the patients were randomly assigned to receive either minoxidil, 2.5 mg twice daily (n = 12), or captopril, 25 mg twice daily (n = 11). In patients with diastolic blood pressure greater than 95 mmHg, doses of minoxidil and captopril were increased in 2-week intervals. Patients who maintained diastolic pressure greater than 95 mmHg and/or those with intolerable side effects were switched over to the alternative substance. After a mean observation period of 12 weeks a significant decrease in systolic and diastolic blood pressure was observed (179/114 vs 148/92 mmHg in the minoxidil group; 176/111 vs 158/97 mmHg in the captopril group). The primary response rate was 75% in patients treated with minoxidil and 55% in those with captopril (not significant). After the change to the alternative substance two of the four non-responders on captopril and one of the two non-responders on minoxidil became responders. Side effects occurred significantly more often during minoxidil than captopril (p less than 0.05). The high efficacy of minoxidil and captopril in the treatment of severe hypertension refractory to conventional drugs was confirmed. Minoxidil lowered blood pressure slightly more than captopril, but it had a higher incidence of side effects than captopril.
 ...
PMID:Minoxidil and captopril in severe hypertension. 352 Jan 32

Minoxidil is very effective in the treatment of severe or resistant hypertension but fluid retention and hypertrichosis have been side-effects. This study examines the suggestion that the use of small doses of minoxidil may be effective in the treatment of moderate hypertension without causing these adverse effects. Sixteen patients with an elevated blood pressure level that was suboptimally controlled by combination therapy with diuretic and beta-adrenoreceptor blocking agents entered a randomized open trial to compare the efficacy and acceptability of minoxidil and prazosin as supplementary therapy to bendrofluazide and metoprolol. Blood pressure control was similar in the two groups. However, relatively large doses of minoxidil were required and over-all tolerance to the drug was poor; five of eight patients who were receiving minoxidil experienced marked fluid retention that necessitated a change in diuretic agent to substantial doses of frusemide. Low doses of minoxidil do not appear to be effective in the treatment of moderate hypertension, and the drug cannot be recommended for this indication.
 ...
PMID:The unsuitability of minoxidil for the treatment of moderate hypertension. 352 2

Of 149 subjects with androgenetic alopecia, 102 completed 1 year of a double-blind, randomized study comparing 2% minoxidil and 3% minoxidil solutions for safety and efficacy. One third of the subjects used a vehicle placebo for the first 4 months and then switched to 3% minoxidil. At 12 months the 2% minoxidil group switched to a 3% solution. During months 5 to 12 a steady increase in terminal hair counts occurred to an equal degree within the 2% and 3% minoxidil groups and the 3% treatment group switched from placebo. Total hair counts at 12 months increased from a baseline mean of 63.5 to 180.6 in the 2% treatment group, from 61.0 to 179.9 in the 3% group, and from 65.0 to 191.1 in the placebo to 3% crossover group. Although all 102 subjects completing 12 months of the study thought that visible hair growth had resulted, 89 were considered by the investigators to have visible growth. Dense hair growth, defined as hair long enough to cut or comb, was present in 48 subjects by their own evaluation and in 33 subjects by investigator evaluation. There were no serious side effects. Two instances of allergic contact dermatitis and four of pruritus were attributed to use of the drug. Two individuals complained of impotence, which disappeared within a few days of discontinuation of topical minoxidil. This effect has not been reported during the use of minoxidil in its oral form (Loniten) for the treatment of hypertension.(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:Safety and efficacy of topical minoxidil in the management of androgenetic alopecia. 354 2


<< Previous 1 2 3 4 5 6 7 8 Next >>